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Quantitative information on the concurrent changes in major rumen microbial functions induced by dietary lipids in relation with the degree of unsaturation of fatty acids is scarce. During a three-period essay (9 days per period), rapeseed (Brassica napus L., RO), sunflower (Helianthus annuus L., SO) and linseed (Linum usitatissimum L., LO) oils at the high level of 80 g/kg dry matter input (DMI) and a control without oil were compared in four 1-L dual outflow fermenters inoculated with bovine rumen microbiota and maintained on a maize silage-based diet. Neither the fermentation medium pH and redox potential nor starch and protein degradabilities were significantly altered. Oil supply significantly decreased butyrate and methane specific productions of to the benefit of propionate and hydrogen specific productions and decreased the microbial protein outflow and synthesis efficiency while increasing the outflows of ammonia and isovalerate, these effects being amplified by the fatty acids' unsaturation degree. Besides, with no impact of the degree of unsaturation, oil supply increased the amount of fermented hexose, the productions of all SCFAs except butyrate and the specific production of acetate. The rumen variables apparently sensitive to oil unsaturation degree were thus related either to metabolic hydrogen removal pathways or to protein metabolism. [ABSTRACT FROM AUTHOR]

Little quantitative information is available on how dietary lipids concurrently alter the main rumen microbial functions in relation with their incorporation level. In a three-period experiment, linseed (Linum usitatissimum, LO) and rapeseed (Brassica napus L., RO) oils were added at 0, 40 or 80 g/kg dry matter input (DMI) to five 1-L dual outflow fermenters that were on a maize silage-based diet for nine days per period. RO supply decreased butyrate specific production. The amount of hexoses fermented (HF) increased by 9% at 40 g/kg LO. The production of CH4 was lower at 80 g/kg LO by 46% compared with controls. Conversely, the supply of LO significantly increased H2 and H2S productions in an antagonistic mode. The specific productions of propionate, butyrate, CH4 and H2 were altered by LO. The supply of RO increased the ammonia daily outflow (by 23% at 40 g/kg) and decreased the organic N outflow (by 13% at 80 g/kg). The degradabilities of dietary fractions were not affected by RO, neither the OM partitioning between dietary, fermented and microbial outflows. The OM true degradability decreased at 80 g/kg LO compared with controls and 40 g/kg LO. When LO was supplied, isovalerate and ammonia-N outflows were higher, organic and microbial N outflows and EMPS were lower along with changes in the OM outflow partitioning. Overall microbial processes appeared to differ in their responses to fatty acids saturation. Moreover, most effects were present at 40 g/kg DMI and diminished or even plateaued at 80 g/kg DMI. Four per cent oil lowered butyrate specific production Four per cent Linseed oil lowered microbial protein synthesis efficiency Linseed oil lowered methanogenesis in proportion to input level [ABSTRACT FROM AUTHOR]

Novel 2‐perfluoroalkylmethyl,4‐arylamino substituted tetrahydroquinolines (THQ) were expeditiously synthesized from perfluoroalkyl iodides RF−I and monosubstituted anilines. First, radical bis‐addition of vinyl acetate on RF−I afforded gem‐iodoacetoxy derivatives (newly characterized by NMR and MS) being actually masked/activated aldol synthons. Their reaction in 1 : 4 ratio with arylamines afforded title THQ under mild conditions in good yields (60–95 %) and diastereoselectivities (65 : 35–95 : 5 cis/trans isomer ratio); m‐substituted anilines regiospecifically lead to 7‐substituted THQ. Mechanistic investigation suggested the THQ formation to proceed through Michael then imine addition of two aniline units on an RF‐substituted crotonaldehyde intermediate, then through the cyclization of the resulting bis(arylamino/imino) intermediate through electrophilic aromatic substitution. Various RF (C6, C2, C4) and arylamine substitutions (p‐,o‐,m‐ alkyl, alkoxyl, halogen...) were thus exemplified. [ABSTRACT FROM AUTHOR]

Two protein tanning methods were evaluated to contribute to the withdrawal of formaldehyde as a tanning agent of meals for feeding ruminants. The experimental materials were two fractions of rapeseed and sunflower meals collected at the positive electrode of an electrostatic separator, presenting high contents in proteins and phenolic compounds. The objective was to make phenolics and proteins interact without addition of exogenous tannins. Treatment CH incubated a meal fraction:water mixture (1:2, w:w) for 48 h at 50 °C. Treatment FR incubated a meal fraction:water mixture (1:10, w:w) at pH 9.0 for 48 h at 4 °C. Microbial proteolysis on meal fractions were quantified during 24 h rumen batch fermentations with cellulose and starch as nitrogen-free energy sources. The net production of ammonia tended to be reduced by treatment FR mostly on rapeseed, corresponding to an 8% saving of rapeseed meal proteins degradable in the rumen. When untreated, the sunflower fraction decreased methane production by 50%, while treatments restored the fermentation pattern. Cold alkaline treatment could be considered to protect meal proteins from degradation by rumen micro-organisms. [ABSTRACT FROM AUTHOR]

The massive influx of refugees into Europe in the past few years has given rise to different kinds of challenges among which is the challenge to successfully communicate with newly arrived immigrants. In this article, we will focus on the public service provision sector where quality of service is to a large extent determined by the capability of a service provider and his or her “client” to understand one another. The article centres on a study involving public organisations providing asylum services or (mental) healthcare services in the multilingual and multicultural city of Brussels. Several interviews were conducted to gain insight into the communication problems such organisations face, as well as their communication requirements and solutions when providing services to people of different linguistic and cultural backgrounds. We will focus on the types of bridging functions commonly deployed by these organisations in multilingual service encounters and on the motivations for using them. In addition, we will discuss the subject of technology-enabled communication in the context of public service provision. Finally, in presenting the results of our study we will formulate specific recommendations on how to improve the use and integration of bridging functions into common service practice. [ABSTRACT FROM AUTHOR]

Colorimetric characterisation systems based on LEDs and RBG sensors are straightforward to implement, are highly integrable allowing for portable measurement systems and can be constructed using widespread and affordable components. They have already proved to be a satisfactory solution in several applications related to chemical analysis. In this paper, we present an RGB sensorbased prototype for colorimetric characterisation, which can accommodate cuvettes with optical paths of 10 mm and 40 mm. We assessed the impact of experimental condition parameters such as the variability of the analyte volume in the cuvette, as well as the presence of floating particles or deposits at the bottom of the cuvette. While these would not impact the result given by a spectrophotometer that generally has a directional light source, they must be considered in LED/RGB sensor analysers in which the light path is not tightly controlled. We demonstrated that there is a minimal sensor height above the bottom of the cuvette and a minimal analyte level (both depending on the prototype optical path length) above which the analyte volume and the presence of floating particles and deposits have no impact on the prototype output signal. Finally, based on these results, we proposed a test method for a quick dye-displacement assay, in which the reagent is a dye-loaded molecularly imprinted polymer that is poured directly into a cuvette. [ABSTRACT FROM AUTHOR]

XGRE (X-ray, Gamma-ray and Relativistic Electrons detector) was one of the main instruments onboard the TARANIS satellite. It is an ultra-fast gamma-ray and electron detector, with a 350 ns dead time, built for measuring Terrestrial Gamma-ray Flashes (TGF). In this paper, we will shortly present the TARANIS mission, the design of the XGRE instrument and the measured performances during the instrument calibration at APC, LESIA and payload calibrations done onboard the satellite at CNES. [ABSTRACT FROM AUTHOR]

The INTEGRAL satellite was launched on October 17, 2002 and all on-board instruments are still operating successfully after more than 12 years, which represents more than a full solar cycle. This paper deals with the dose measured by 8 RadFETs mounted in 2 electronic boxes, which control the detector plane of the IBIS/ISGRI camera. These measurements are compared to what could be predicted before the launch, by using the dose profile, as determined by common space environment software, and also a detailed sectorial analysis of shielding materials around the RadFETs by means of a Monte-Carlo based model of the whole spacecraft. In this study, the sectorial analysis relies on the accurate knowledge of the geometry, as determined from the qualification model of the electronic box still in the lab. In order to take into account the orbit evolution with time, the dose profile is determined with yearly-averaged orbital parameters for each of the 12 years of measurements. The aim of this analysis is to estimate the possibility of releasing some margins for future projects. [ABSTRACT FROM PUBLISHER]

Proposed in 1997, the ACES/PHARAO experiment is a space mission in fundamental physics with two atomic clocks on the International Space Station, a network of ultra-stable clocks on the ground, and space-to-ground time transfer systems. The ACES flight instruments are near completion and launch in space is planned for the first half of 2017 for a mission duration of three years. A key element of the satellite payload is a cold-atom clock designed for microgravity environment, PHARAO, operating with laser-cooled cesium atoms. Here we first report on the design and tests of the PHARAO flight model, which is now completed and ready for launch. We then briefly present the status of development of the other instruments of the ACES payload, the Space Hydrogen Maser, the microwave time-transfer system (MWL), and the laser time transfer ELT. [ABSTRACT FROM AUTHOR]

We designed a 3D geometrical model of a metal-oxide gas sensor and its custom packaging and used it in finite element modeling (FEM) analysis for obtaining temperature and heat flux distribution. The 3D computer simulation, performed with GetDP software (version 3.5.0, 13 May 2022), accurately predicted the temperature distribution variation across the entire assembly. Knowing the temperature variation and the location of the hot spots allowed us to select the best electrical interconnect method and to choose the optimal materials combination and optimal geometry. The thermal modeling also confirmed the need to use a low thermal conductivity material to insulate the MOX sensor since the latter is heated to its operational temperature of 250 °C. For that purpose, we used the in-house formulated xerogel–epoxy composite of thermal conductivity of 0.108 W m−1 K−1, which is at least 30% less compared to the best-in-class among commercially available materials. Based on the 3D FEM outputs, we designed, assembled, and characterized a fully functional packaged MOX gas sensor in several configurations. We measured the temperature distribution on all parts of the MOX gas sensor assembly using a thermal imaging infrared (IR) microscope. The results of 3D FEM are in good agreement with the temperature distribution obtained by the non-contact IR thermal characterization. [ABSTRACT FROM AUTHOR]

The space clock PHARAO is an atomic clock based on laser cooled cesium atoms. In order to attenuate magnetic field fluctuation in orbit, PHARAO clock uses three concentric Mumetal magnetic shields combined with several coils to improve the field homogeneity. We have characterized the attenuation and magnetic field homogeneity of the shields used to build the flight model. The average value of attenuation inside the three shields is around 18,000 when the external field is similar to the orbit field (30µT) and the field homogeneity is lower than 10nT. These values have not changed after vibrations and thermal tests for the space qualification. Permeability variation of the shields as a function of the intercepted flux has been analyzed. [ABSTRACT FROM AUTHOR]

Abstract: We report a new synthesis and our study of the mechanism of formation of substituted 1-trifluoromethyl and 1-perfluoroalkyl-3-(phenylamino)prop-2-en-1-one starting from 3-(R-phenoxy)-3-perfluoroalkyl-prop-2-enals and arylamines. Reactivity study of the intermediates confirmed that 3-perfluoroalkyl-N,N′-diphenyl-1,5-diazapentadienes are the synthetic intermediates of the synthesis of 2-perfluoroalkylquinolines. The mechanism of the reaction of 1-trifluoromethyl and 1-perfluoroalkyl-3-(phenylamino)prop-2-en-1-one with POCl3 was studied. To our knowledge this is the first detection and isolation of N,N′-diaryldiazapentadiene derivatives as intermediates in the Combes F-alkyl substituted quinoline synthesis starting from enaminoketones. Finally, we succeeded isolating and identifying unsymmetrically substituted 2-perfluorolakyldiazapentadiene. [Copyright &y& Elsevier]

In 2003, Google made available in Belgium its online free service "Google News", which consisted in offering Internet users a computer-generated press review. In his orders of 5 September 2006 (previously commented in [2007] 23 CLSR 82-85) and of 13 February 2007 (previously commented in [2007] 23 CLSR 290-293) the President of the High Court of Brussels found that, by offering this service, Google infringed the copyrights of Belgian press editors and authors. On 5 May 2011, the Brussels Court of Appeal upheld to a very large extent the first instance decision. The Court confirmed that Google's "cache" function and its "Google News" service were infringing the claimants' copyrights and that Google could not rely on any copyright limitation (such as the exceptions for quotation or for report on news events), legislation or fundamental right. [ABSTRACT FROM AUTHOR]

Abstract: In the present pilot study, intradermal ID delivery systems with a BD microneedle from 1 to 3mm in length, and epidermal delivery (BD skin abrader) through abraded skin surface relative to standard intramuscular injection were evaluated. Circulating neutralizing antibodies were measured against the rabies virus after the Vero cells rabies vaccine was administered at D0, D7, D21 and D49. This clinical evaluation in 66 healthy volunteers shows that ID delivery using BD microneedle technology of 1/4 the IM antigen dose is safe, efficient and reliable, resulting in a protective seroconversion rate. In contrast, the epidermal delivery route did not produce an immune response against the rabies vaccine. [ABSTRACT FROM AUTHOR]

The development of an efficient and general trifluoro�methylation or perfluoroalkylation method is a major challenge in organic chemistry. This Account presents the breakthrough realized in this field using polyfluoroalkylated gem-iodoacetoxy derivatives which are useful synthons for the short preparation of various fluorinated organic compounds. The main body of this Account highlights several applications of these new derivatives as starting blocks for diverse regiospecific syntheses of trifluoromethyl- and perfluoroalkyl-containing heterocyclic compounds. A brief discussion of the use of a new method for the determination of the configuration and conformation of push-pull perfluoroalkyl-containing olefinic derivatives using coupling constant 4JCF is included. 1 Introduction 2 Synthesis of α-Iodoalkyl Esters, R�R�C(I)OCOR� 3 Reactivity of Polyfluoroalkylated gem-Iodoacetoxy Derivatives 3.1 Synthesis of 2-(Perfluoroalkyl)ethanals 3.2 Chemoselective Reactions 3.3 Reactivity Towards Nitrogen Compounds 3.4 Reactivity Towards Phenol Derivatives 3.5 Determination of the Stereochemistry of Push-Pull Derivatives Using a Through-Space Coupling Constant: 4JCF 4 Summary and Outlook [ABSTRACT FROM AUTHOR]

Abstract: There has been a recent resurgence of interest in intradermal vaccine delivery. The physiological advantages of intradermal vaccine delivery have been known for some time, but the difficulties associated with performing an intradermal injection have historically limited its use. New delivery systems currently in development facilitate convenient intradermal vaccination, unlocking the potential advantages of this delivery route, and potentially transforming vaccine delivery. [Copyright &y& Elsevier]

Abstract: The advantages of intradermal (ID) vaccine administration have been well documented but difficulties in performing ID vaccination using existing techniques and equipment have limited it''s clinical application. In the present study, a new ID injection technique and associated microinjection system is described and evaluated in a swine and Human models. Clinical investigation models included: injection site imaging (X-ray and 3D ultrasound echography), histological examination of injection sites, fluid injection volume accuracy measurement, subject’ perceived pain and local skin reactivity were specifically developed. These evaluations showed that microinjection system can make the practice of ID vaccination easy to perform, reliable and safe, thus setting the stage for broader clinical application of ID vaccine delivery. [Copyright &y& Elsevier]

Abstract: Since 2003, Google has made available in Belgium its online free service “Google News”, which consists of offering Internet users a computer-generated press review. In his default order of 5 September 2006 (previously commented in [2007] 23 CLSR 82–85), the President of the High Court of Brussels found that, by offering this service, Google infringed the rights of Belgian newspapers. In its order of 13 February 2007 delivered upon opposition, the same jurisdiction confirms the copyrights infringement and partially withholds its decision. [Copyright &y& Elsevier]

Abstract: Since 2003, the Google search engine has made available in Belgium its online free service “Google News”, which consists of offering Internet users a computer-generated press review. This case note considers the order of the President of the High Court of Brussels, in which it was found that, by offering this service, Google infringed the copyrights and sui generis database rights of Belgian newspapers. [Copyright &y& Elsevier]

Abstract: The relationship between deformation and so-called fluid paleotransfers in minor faults has been analysed in an argillaceous formation located in the Causses Basin in France. The fluid paleotransfers are related to the fault activity to a large extent. We attempt to estimate the intensity of paleo-deviatoric stress magnitudes under which the fault activity may have occurred and consequently, the change in the structural fault permeability. The paleo-deviatoric stress magnitudes were calculated with the inverse method of Etchecopar applied to calcite twinning. The measured crystals are contained within the core zone of minor faults and this study is based on a previous complete microtectonic and microstructural analysis of the faults. In this paper, analysis of calcite twinning has been applied for the first time to vein fillings associated small faults in a context of relatively weak deformation, a condition ensured by the tectonic and structural analysis. Calculation and discussion of the paleo-deviatoric stress tensors in relation to the evolution of the structural fault permeability and to the hydraulic behaviour of the faults are the aim of this paper. The analysed faults, created and active during the same tectonic event, were permeable under a (σ 1–σ 3) mean value of 40–50 MPa. On the other hand, the reactivation of faults during a second tectonic event implies mean (σ 1–σ 3) value higher than 40–50 MPa, especially for the faults that are poorly oriented with respect to the principal tectonic stress directions. The core zone of these faults remained sealed and impermeable or became permeable by development of microcracks inside the pre-existing fillings. [Copyright &y& Elsevier]

The synthesis of substituted 2-(trifluoromethyl)- and 2-(perfluoroalkyl)-2-hydroxy-2H-chromenes 2a-o was achieved in good yields by intramolecular cyclization of 3-(perfluoroalkyl)-3-phenoxypropenals 1 in the presence of aluminum chloride. Then a Lewis acid mediated nucleophilic reaction with silyl enol ethers 3 proceeded with complete regiospecificity to afford 4-functional 2-(trifluoromethyl)- and 2-(perfluoroalkyl)-4H-chromenes 4a-p with high yields. [ABSTRACT FROM AUTHOR]

Substituted 3-phenoxy-3-perfluoroalkylprop-2-enals 3a-s are synthesized in high yields starting from a gem-iodoacetoxy derivative 1 and phenoxides 2. Then efficient syntheses of push-pull derivatives 4, 5, 8a,b, and nonconjugated analogues 6 and 7 illustrate the synthetic potentialities of 3. Stereochemical studies of these perfluoroalkyl-containing trisubstituted olefinic derivatives 3-8b revealed that the 4JCF coupling constant observed in the 13C NMR spectra was crucial in the determination of their configurations and conformations in solution. The solvent polarity effect on the stereochemistry of push-pull compounds 3–5 and 8a,b was studied. Unusual significant medium polarity effect on the stereochemistry of imino enol ether derivative 4 was observed. [ABSTRACT FROM AUTHOR]

Efficient control of Xanthomonas axonopodis pv. dieffenbachiae, the causal agent of anthurium bacterial blight, requires a sensitive and reliable diagnostic tool. A nested PCR test was developed from a sequence-characterized amplified region marker identified by randomly amplified polymorphic DNA PCR for the detection of X. axonopodis pv. dieffenbachiae. Serological and pathogenicity tests were performed concurrently with the nested PCR test with a large collection of X. axonopodis pv. dieffenbachiae strains that were isolated worldwide and are pathogenic to anthurium and/or other aroids. The internal primer pair directed amplification of the expected product (785 bp) for all 70 X. axonopodis pv. dieffenbachiae strains pathogenic to anthurium tested and for isolates originating from syngonium and not pathogenic to anthurium. This finding is consistent with previous studies which indicated that there is a high level of relatedness between strains from anthurium and strains from syngonium. Strains originating from the two host genera can be distinguished by restriction analysis of the amplification product. No amplification product was obtained with 98 strains of unrelated phytopathogenic bacteria or saprophytic bacteria from the anthurium phyllosphere, except for a weak signal obtained for one X. axonopodis pv. allii strain. Nevertheless, restriction enzyme analysis permitted the two pathovars to be distinguished. The detection threshold obtained with pure cultures or plant extracts (10³ CFU ml-1) allowed detection of the pathogen from symptomless contaminated plants. This test could be a useful diagnostic tool for screening propagation stock plant material and for monitoring international movement of X. axonopodis pv. dieffenbachiae. [ABSTRACT FROM AUTHOR]

Using a 214–10 fractional factorial design, 13 plant extracts containing flavonoids were screened to determine their influence on rumen microbial metabolism in continuous culture systems. Each extract was supplied at the rate of 0.5 g per day, which corresponded to a concentration of 15 g kg−1 dietary dry matter (DM). Outflow of VFA was enhanced with Lavandula officinalis (+9.8%) and Solidago virga-aurea (+6.4%), but starch degradability was not modified, while NDF and ADF degradabilities increased with Achillea millefolium and decreased with Betula alba and Equisetum arvense. True degradability of crude protein (CP) increased with A. millefolium (+5.8%) and Dactylis glomerata (+6.1%), and decreased with Arnica chamissonis (−5.8%) and L. officinalis (−7.1%). Net production of microbial protein increased by 8.7% with A. millefolium. Efficiency of microbial protein synthesis was improved by A. millefolium (+10% from a basal value of 27.7 g N kg−1 FOM), and lowered by L. officinalis (−12.3%). Initiating a sequential experimental approach by a moderately sized 214–10 design allowed us to isolate L. officinalis, and S. virga-aurea on the basis of their stimulating effect on fermentation, and A. millefolium for increasing both degradabilities of CP and cell-wall constituents and efficiency and yield of biomass production. The information gained at this first step must now be reassessed with a full resolution design, which will protect against misinterpretations due to interactions among the three remaining plant extracts. [Copyright &y& Elsevier]

Reports on the development of a compact, transportable and reliable space cold atom clock prototype designed to operate on earth or in microgravity environment. Description of the prototype; Experimental results in parabolic flights; Evaluation of the microwave cavity.

Deals with a study that simulated effects of the electrons free-falling motions on the resulting Comptonized spectrum as well as the general relativistic effects close to the black hole. Geometries used in the Monte Carlo simulations; Parameters of the simulations; Correlation between thermal temperature and resulting spectra.

An active shield using a scintillator and silicon photo-multipliers (SiPMs) has been developed to operate with space environment particle detectors sensitive to both protons and electrons, such as Influence sur les Composants Avancés des Radiations de l’Espace-Nouvelle Génération (ICARE-NG). The method shows a reduction in electron contamination through the sides of the detector, thus increasing energy resolution. Two geometries are studied, one working in coincidence mode with the main detector and the other in anti-coincidence. Performances of both the geometries are simulated in proton and electron environments in energy ranges typical of a space environment. Experimental measurements then aimed to validate the Monte Carlo simulation framework for scintillating materials. Finally, a case study of electron decontamination is carried out, as well as an error rate estimation in flux reconstruction. [ABSTRACT FROM AUTHOR]

We report a new one-pot synthesis of 2-trifluoromethylated/2-perfluoroalkylated N-aryl-substituted pyridiniums, 5,6,7,8-tetrahydroquinoliniums and 6,7,8,9-tetrahydro-5H-cyclohepta[b]-pyridinium compounds starting from an activated β-dicarbonyl analogue (here a perfluoro-alkylated gem-iodoacetoxy derivative), an aromatic amine and a (cyclic or acyclic) ketone. The key step of this multicomponent reaction, involves the formation of a 3-perfluoroalkyl-N,N'-diaryl-1,5-diazapentadiene intermediate, various examples of which were isolated and characterized for the first time, together with investigation of their reactivity. We propose a mechanism involving a concurrent inverse electron demand Diels-Alder or Aza-Robinson cascade cyclisation, followed by a bis-de-anilino-elimination. Noteworthy, a meta-methoxy substituent on the aniline directs the reaction towards a 2-perfluoroalkyl-7-methoxyquinoline, resulting from the direct cyclization of the diazapentadiene intermediate, instead of pyridinium formation. This is the first evidence of synthesis of pyridinium derivatives from activated β-dicarbonyls, ketones, and an aromatic amine, the structures of which (both reactants and products) being analogous to species involved in biological systems, especially upon neurodegenerative diseases such as Parkinson's. Beyond suggesting chemical/biochemical analogies, we thus hope to outline new research directions for understanding the mechanism of in vivo formation of pyridiniums, hence possible pharmaceutical strategies to better monitor, control or prevent it. [ABSTRACT FROM AUTHOR]

In some specific microelectronic applications, there is a demand for adhesive materials (glues/encapsulants) having very good thermal insulation properties. We have studied the properties obtained on epoxy-based samples loaded by several levels of xerogel filling. The thermal conductivity of these materials depends on the exact chemical composition and their manufacturing process. As a result, the thermal conductivity given in the manufacturer’s specifications or in the literature generally exhibits some dispersion. Therefore, we have developed a straightforward experimental rig, based on a vacuum chamber and miniature Pt100 sensors measurements, to precisely know the thermal conductivity of the various insulating materials used in the development and the assembly of select microsensors and microsystems. The results showed a decrease in the thermal conductivity of our xerogel-epoxy composites up to 35.8% compared with the value of the unfilled epoxy, corresponding to a thermal conductivity value of 107.9 mW m−1 K−1. In addition, cross-sectional images were observed by optical microscopy to characterize the specific microstructure of each sample to relate these observations to improvements in thermal conductivity. [ABSTRACT FROM AUTHOR]

Aims. We investigate a two-temperature advective transonic accretion disc around a black hole and analyse its spectrum in the presence of radiative processes such as bremsstrahlung, synchrotron, and inverse-Comptonisation. The aim is to link the emergent spectra with constants of motion of the accretion disc fluid, however, the number of unknowns in two-temperature theory exceeds the number of equations for a given set of constants of motion. We intend to remove the degeneracy using a general methodology and obtain a unique solution, along with its spectrum. Methods. We used hydrodynamic equations (continuity, momentum, and energy conservation equation) to obtain sonic points and solutions. To solve these equations of motion we used the 4th order Runge-Kutta method. For the spectral analysis, general and special relativistic effects were taken into consideration. The system is, nonetheless, degenerate and we remove the degeneracy by choosing the solution with maximum entropy, as dictated by the second law of thermodynamics. Results. We obtained a unique transonic solution for a given set of constants of motion. The entropy expression is a tool used to make a selection between the degenerate solutions. We found that Coulomb coupling is a weak energy exchange term, which allows protons and electrons to settle down into two different temperatures, justifying, hence, our study of two-temperature flows. The information of the electron flow allows us to model the spectra. We show that the spectra of accretion solutions depend on the associated constants of motion. At low accretion rates, bremsstrahlung is important. A fraction of the bremsstrahlung photons may be of higher energy than the neighbouring electrons, energising them through the process of Compton scattering. Synchrotron emission, on the other hand, provides soft photons, which can be inverse-Comptonised to produce a hard power law part in the spectrum. Luminosity increases with the increase in the accretion rate of the system, as well as with the increase in BH mass. However, the radiative efficiency of the flow has almost no dependence on the BH mass, but it sharply rises with the increase in the accretion rate. The spectral index, however, hardens with the increase in the accretion rate, while it does not change much with the variation in BH mass. In addition to the constants of motion, the value of the plasma beta parameter and magnitude of magnetic dissipation in the system also helps in shaping the spectrum. A shocked solution exists in two-temperature accretion flows in a limited region of the parameter space. We find that a shocked solution is always brighter than a solution without a shock. Conclusions. An accreting system in two-temperature regime admits multiple solutions for the same set of constants of motion, producing widely different spectra. Comparing the observed spectrum with that derived from a randomly chosen accretion solution would give us a wrong estimation of the accretion parameters of the system. The form of entropy measurement we obtained helped us to remove the degeneracy of the solutions and allowed us to understand the physics of the system, shorn of arbitrary assumptions. In this work, we show how the spectra and luminosities of an accreting system depend on the constants of motion, producing solutions ranging from radiatively inefficient flows to luminous flows. An increase in BH mass quantitatively changes the system, making the system more luminous, while the spectral bandwidth also increases. A higher BH mass system spans the range from radio to gamma-rays. However, increasing the accretion rate around a BH of certain mass has little influence on the frequency range of the spectra. [ABSTRACT FROM AUTHOR]

Abstract This work presents a long-term operation of two stacked CdTe double sided strip detectors that are comparable with the CdTe detectors onboard Hitomi's HXI. The goal of this test is to study the evolution of the spectroscopic performance of the detectors during a one year operation cycle which resembles the in-orbit operation cycle of Hitomi HXI. Crystal defects inside CdTe cause a degradation of the spectroscopic performance (polarization effect) of the crystal which is becoming worse during detector operation. In order to prevent crystal polarization, the detectors are reset (switch-off of the depletion voltage) once a day. Our main investigation was to study if a long-term degradation can occur as a result of incomplete depolarization during the reset. We present the hardware setup and the analytical steps that were used to investigate the detector stability during each day and over the whole testing period. For the anode signals our results show at 60 keV: a daily line drift of (− 2. 8 ± 0. 7) eV/ks while the long-term drift is (− 1. 5 ± 1. 2) eV/day. The degradation of the energy resolution is measured to be (+ 2. 4 ± 0. 3) eV/ks FWHM and the loss of efficiency is (− 0. 29 ± 0. 02) %/ks. [ABSTRACT FROM AUTHOR]

Abstract: This work reports on the use of molecular translocators to capture a dibenzo‐24‐crown‐8 (DB24C8) and then release it onto targeted molecular axles to afford, after removal of the translocator, [2]rotaxanes that do not hold any template site. Various translocators were studied and successfully aided the synthesis, with more or less efficacy, of [2]rotaxanes of different lengths. During the releasing step, the DB24C8 macrocycle shuttles along the thread, and the localization of the macrocycle might be driven by steric repulsion on the translocator part and/or electronic attraction of the targeted part of the axle to be encircled, which depends on both the nature of the translocator and the targeted thread to be encircled. [ABSTRACT FROM AUTHOR]

The effect of the primeval sources of radiation and particles on the thermodynamical state of the intergalactic medium during the epoch of reionization is still unclear. In this work, we explore the contribution of electrons accelerated in the jets of high-redshift microquasars to heating and ionizing the intergalactic medium. We develop Monte Carlo simulations of the propagation and energy deposition of these electrons as they travel away from their sources. We find that microquasars contribute significantly to heating the intergalactic medium and are effective ionizers only near the galaxies. Their effect on heating is of the same order of magnitude as that of cosmic rays from supernovae. [ABSTRACT FROM AUTHOR]

Here is reported the synthesis and characterization of an interlocked figure‐of‐eight rotaxane molecular shuttle from a dibenzo‐24‐crown‐8 (DB24C8) derivative. This latter bears two molecular chains, whose extremities are able to react together by click chemistry. One of the two substituting chain holds an ammonium function aimed at driving the self‐entanglement through the complexation of the DB24C8 moiety. In the targeted figure‐of‐eight rotaxane, shuttling of the DB24C8 along the threaded axle from the best ammonium station to the weaker binding site triazolium was performed through deprotonation or deprotonation‐then‐carbamoylation of the ammonium. This way, two discrete co‐conformational states were obtained, in which the folding and size of the two loops could be changed. [ABSTRACT FROM AUTHOR]

Here is reported the synthesis and characterization of an interlocked figure‐of‐eight rotaxane molecular shuttle from a dibenzo‐24‐crown‐8 (DB24C8) derivative. This latter bears two molecular chains, whose extremities are able to react together by click chemistry. One of the two substituting chain holds an ammonium function aimed at driving the self‐entanglement through the complexation of the DB24C8 moiety. In the targeted figure‐of‐eight rotaxane, shuttling of the DB24C8 along the threaded axle from the best ammonium station to the weaker binding site triazolium was performed through deprotonation or deprotonation‐then‐carbamoylation of the ammonium. This way, two discrete co‐conformational states were obtained, in which the folding and size of the two loops could be changed. [ABSTRACT FROM AUTHOR]