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Super-Earths transiting nearby bright stars are key objects that simultaneously allow for accurate measurements of both their mass and radius, providing essential constraints on their internal composition. We present the confirmation, based on Spitzer observations, that the super-Earth HD 97658 b transits its host star. HD 97658 is a low-mass (M* = 0.77 ± 0.05 M⊙) K1 dwarf, as determined from the Hipparcos parallax and stellar evolution modeling. To constrain the planet parameters, we carry out Bayesian global analyses of Keck-HIRES radial velocities, and MOST and Spitzer photometry. HD 97658 b is a massive (MP = 7.55−0.79+0.83 M⊕) and large (RP = 2.247−0.095+0.098 R⊕ at 4.5 μm super-Earth. We investigate the possible internal compositions for HD 97658 b. Our results indicate a large rocky component, by at least 60% by mass, and very little H-He components, at most 2% by mass. We also discuss how future asteroseismic observations can improve the knowledge of the HD 97658 system, in particular by constraining its age.

We present the status of an ongoing program which aim at measuring occultations by their parent stars of transiting hot giant exoplanets discovered recently by Kepler. The observations are obtained in the near infrared with WarmSpitzer Space Telescope and at optical wavelengths by combining more than a year of Kepler photometry. The investigation consists of measuring the mid-occultation times and the relative occultation depths in each band-passes. Our measurements of occultations depths in the Kepler bandpass is turned into the determination of the optical geometric albedo Ag in this wavelength domain. The brightness temperatures of these planets are deduced from the infrared observations. We combine the optical and near infrared planetary emergent fluxes to obtain broad band emergent spectra of individual planet. We finally compare these spectra to hot Jupiter atmospheric models in order broadly distinguishing these atmospheres between different classes of models.

Atmospheric arc discharge volumes have been estimated from the light distribution emitted during evaporation of graphite and molybdenum disulphide (MoS2) anodes. These data have been correlated to the peak power in the case of pulsed arc discharge held at different frequencies (1, 2, and 5 Hz). The measured power density values and the corresponding specific energies per particle have been compared to DC values and showed that pulsed arc discharges deliver electrical power more efficiently than DC arc discharges do with yet lower thermal loads. In particular, the power density of approximately 1 kW/cm3 characteristic of pulsed arcs (10–20 kW/cm3 in DC) suffices to provide 15 eV/particle to the arc plasma (approximately 10 eV/particle or less in DC). Such an energy balance resulted in high ionization rates of the ablated material and production yields of carbon nanotubes around 1011 cm−2 kWh−1. Finally, in situ probe experiments showed that pulsed arcs enhance the transport to the substrate of the generated nanoparticles, such as graphene and MoS2 monolayers. Pulsed anodic arcs open the possibility to generate further nanomaterials thanks to a more rational power investment and a better control of the discharge region. [ABSTRACT FROM AUTHOR]

The dynamics of nanoparticle growth in pulsed anodic arc discharge has been studied in time-resolved mode. To this end, a fast moving probe was employed to extract the material generated in a pulsed arc plasma held between two graphite electrodes. The probe motion was synchronized with the pulse phase and the exposure time to the plasma was set to 10 ms. The graphite anode was eroded in a helium atmosphere (300 Torr) by an arc plasma pulsed at 1 Hz with a 10% duty cycle and showing 250 A of peak current. The structure and morphology of the probe depositions were characterized by Raman spectroscopy, scanning electron microscopy, and focused ion beam. A maximal deposition rate of 260 μm/s was measured 5 mm away from the arc core during the active 0.1 s of the pulse. Such a rate yields a growth flux of 1.3 × 1021 cm−2 s−1, rich in carbon nanostructures (graphene platelets, nanotubes) with a characteristic aggregate size within 1–10 μm. The deposition during the inactive 0.9 s of the pulse was several orders of magnitude slower and consisted of amorphous carbon traces. Moreover, the nanoparticle distribution along the collecting probe is correlated with the pulse phase, thereby providing information on particle transport. Pulsed nanosynthesis can be modeled as a periodical growth process, where the volume and propagation velocity of the growth region can be adjusted through modulation of the pulse signal waveform. The proposed model constitutes a suitable framework to investigate the pulsed arc synthesis of nanomaterials with tailored physical and chemical properties. [ABSTRACT FROM AUTHOR]

Plasma technology is actively used for nanoparticle synthesis and modification. All plasma techniques share the ambition of providing high quality, nanostructured materials with full control over their crystalline state and functional properties. Pulsed-DC physical/chemical vapour deposition, high power impulse magnetron sputtering, and pulsed cathodic arc are consolidated low-temperature plasma processes for the synthesis of high-quality nanocomposite films in vacuum environment. However, atmospheric arc discharge stands out thanks to the high throughput, wide variety, and excellent quality of obtained stand-alone nanomaterials, mainly coreâ€"shell nanoparticles, transition metal dichalcogenide monolayers, and carbon-based nanostructures, like graphene and carbon nanotubes. Unique capabilities of this arc technique are due to its flexibility and wide range of plasma parameters achievable by modulation of the frequency, duty cycle, and amplitude of pulse waveform. The many possibilities offered by pulsed arc discharges applied on synthesis of low-dimensional materials are reviewed here. Periodical variations in temperature and density of the pulsing arc plasma enable nanosynthesis with a more rational use of the supplied power. Parameters such as plasma composition, consumed power, process stability, material properties, and economical aspects, are discussed. Finally, a brief outlook towards future tendencies of nanomaterial preparation is proposed. Atmospheric pulsed arcs constitute promising, clean processes providing ecological and sustainable development in the production of nanomaterials both in industry and research laboratories. [ABSTRACT FROM AUTHOR]

Anatomical variations in the median nerve have been extensively documented since the inception of carpal tunnel surgery. We report a dual anatomic variation in the median nerve encountered during the carpal tunnel decompression. The bifid median nerve was associated with preligamentous thenar motor branch arising from the ventral aspect of the radial portion of the median nerve, remaining deep to antebrachial fascia and then piercing the transverse carpal ligament to reach the thenar muscles. Lanz described the various anomalies of the median nerve in the carpal tunnel and classified the bifid median nerve as group III. Various abnormalities associated with the bifid median nerve are further classified by Al-Qattan et al and classified the bifid median nerve associated with aberrant nerve branches as group VI. [ABSTRACT FROM AUTHOR]

Iatrogenic injury to the thenar motor branch of median nerve, though rare, is a serious complication during carpal tunnel decompression. The incidence is high when there is variation in the thenar motor branch and hence we should be aware of the common as well as unusual and rare anatomical variants. As uncommon variations render the thenar branch more prone for iatrogenic injury knowing more would surely save one’s day while doing a carpal tunnel release. We present a rare anatomical variant of the thenar motor branch of the median nerve that we encountered during open carpal tunnel release. The thenar motor branch was originating from the ulnar side of the median nerve proximal to the transverse carpal ligament, traversing subligamentous and joining a communicating branch from the median nerve distal to the transverse carpal ligament. The nerve was accidentally cut intraoperatively, which was immediately identified and repaired. At the postoperative follow-up after 6 months, patient has recovered thenar function with the ability to write with his right hand with good opposition. [ABSTRACT FROM AUTHOR]

We present radio observations made towards the exoplanets Qatar-1b and WASP-80b near 150 MHz with the Giant Meterwave Radio Telescope (GMRT). These targets are relatively nearby irradiated giant exoplanets, a hot Jupiter and a hot Saturn, with sizes comparable to Jupiter but different masses and lower densities. Both the targets are expected to host extended H/He envelopes like Jupiter, with comparable or larger magnetic moments. No radio emission was detected from these exoplanets, with 3σ limits of 5.9 and 5.2 mJy for Qatar-1b and WASP-80b, respectively, from these targeted observations. These are considerably deeper limits than those available for exoplanets from wide-field surveys at similar frequencies. We also present archival Very Large Array (VLA) observations of a previously reported radio source close to 61 Vir (which has three exoplanets). The VLA observations resolve the source, which we identify as an extragalactic radio source, i.e. a chance association with 61 Vir. Additionally, we cross-match a recent exoplanet catalogue with the TIFR GMRT Sky Survey ADR1 radio catalogue, but do not find any convincing associations. [ABSTRACT FROM AUTHOR]

Optical transmission spectroscopy provides crucial constraints on the reference pressure levels and scattering properties for the atmospheres of hot Jupiters. For certain planets, where alkali atoms are detected in the atmosphere, their line profiles could serve as a good probe to link upper and lower atmospheric layers. The planet WASP-21b is a Saturn-mass hot Jupiter orbiting a thick-disk star, with a low density and an equilibrium temperature of 1333 K, which makes it a good target for transmission spectroscopy. Here, we present a low-resolution transmission spectrum for WASP-21b based on one transit observed by the OSIRIS spectrograph at the 10.4 m Gran Telescopio Canarias (GTC), and a high-resolution transmission spectrum based on three transits observed by HARPS-N at Telescopio Nazinale Galileo (TNG) and HARPS at the ESO 3.6 m telescope. We performed spectral retrieval analysis on GTC's low-resolution transmission spectrum and report the detection of Na at a confidence level of >3.5-σ. The Na line exhibits a broad line profile that can be attributed to pressure broadening, indicating a mostly clear planetary atmosphere. The spectrum shows a tentative excess absorption at the K D1 line. Using HARPS-N and HARPS, we spectrally resolved the Na doublet transmission spectrum. An excess absorption at the Na doublet is detected during the transit, and shows a radial velocity shift consistent with the planet orbital motion. We proposed a metric to quantitatively distinguish hot Jupiters with relatively clear atmospheres from others, and WASP-21b has the largest metric value among all the characterized hot Jupiters. The detection of Na both in the lower and upper atmospheres of WASP-21b reveals that it is an ideal target for future follow-up observations, providing the opportunity to understand the nature of its atmosphere across a wide range of pressure levels. [ABSTRACT FROM AUTHOR]

Pulsed anodic arc discharge is a novel synthesis method of nanomaterials by means of low-temperature atmospheric plasma. The technique consists in periodically supplying DC power to two vertically aligned electrodes in the form of short unipolar pulses with peak currents of a few hundred Amperes in a helium atmosphere. The pulsed arc plasmas are sustained at frequencies on the order of 1 Hz with around 10% of duty cycle. It constitutes a versatile technique thanks to a series of advantages compared to continuous DC arc processes, in particular, flexibility in the experimental conditions, process stability and repeatability, better utilization of ablating anode material, lower production of macroparticles, and lower thermal loads. Such features are discussed in this article. A brief overview concerning the recent accomplishments of pulsed arc discharge on deposition of carbon nanostructures (graphene and carbon nanotubes) and few-layer flakes of molybdenum disulphide and an outlook on future applications of this method for the discovery of new materials with tailored functional properties are provided. [ABSTRACT FROM AUTHOR]

The work carried out is focused on study and behavior of rotors and to check the reliability at the design stage using the advanced XLrotor tool. For the selected rotor, the failures are controlled by shifting critical speeds above the maximum speed in which it is designed for. The rotor is balanced with safe limits of vibration severity criteria as per ISO standards for an optimized model. Sensitivity analysis is carried out on the rotor model by varying factors such as the diameter of shaft, disk configuration, disk offset, and load on rotor model. The results obtained show good agreement with the FEM results. The results obtained are undamped & damped critical speeds, as well as velocity & dynamic load on bearings due to imbalance using XLrotor. The rotor model is balanced for a steel shaft with a steel disk as well as a steel shaft with an aluminum disk (optimized rotor model) as part of the corrective method. The work clearly emphasizes XLrotor for designing a highly reliable rotor that is safe for operating conditions. [ABSTRACT FROM AUTHOR]

There has been increasing progress toward detailed characterization of exoplanetary atmospheres, in both observations and theoretical methods. Improvements in observational facilities and data reduction and analysis techniques are enabling increasingly higher quality spectra, especially from ground-based facilities. The high data quality also necessitates concomitant improvements in models required to interpret such data. In particular, the detection of trace species such as metal oxides has been challenging. Extremely irradiated exoplanets (~3000 K) are expected to show oxides with strong absorption signals in the optical. However, there are only a few hot Jupiters where such signatures have been reported. Here we aim to characterize the atmosphere of the ultra-hot Jupiter WASP-33 b using two primary transits taken 18 orbits apart. Our atmospheric retrieval, performed on the combined data sets, provides initial constraints on the atmospheric composition of WASP-33 b. We report a possible indication of aluminum oxide (AlO) at 3.3-σ significance. The data were obtained with the long slit OSIRIS spectrograph mounted at the 10-m Gran Telescopio Canarias. We cleaned the brightness variations from the light curves produced by stellar pulsations, and we determined the wavelength-dependent variability of the planetary radius caused by the atmospheric absorption of stellar light. A simultaneous fit to the two transit light curves allowed us to refine the transit parameters, and the common wavelength coverage between the two transits served to contrast our results. Future observations with HST as well as other large ground-based facilities will be able to further constrain the atmospheric chemical composition of the planet. [ABSTRACT FROM AUTHOR]

We present 10 high-precision light curves of four transits in the XO-1 planetary system, obtained using u, g, r, redshifted H α, I, and |$z$| filters. We use these to measure the physical properties, orbital ephemeris, and a transmission spectrum of the planet covering the full optical wavelength range. We augment this with published HST /WFC3 observations to construct a transmission spectrum of the planet covering 0.37–1.65 |$\mu$| m. Our best-fitting model to this spectrum is for a H2/He-rich atmosphere containing water (3.05σ confidence), nitrogen-bearing molecules NH3and HCN (1.5σ) and patchy cloud (1.3σ). We find that adding the optical to the near-infrared data does not lead to more precise constraints on the planetary atmosphere in this case. We conduct a detailed investigation into the effect of stellar limb darkening on our results, concluding that the choice of limb darkening law and coefficients is unimportant; such conclusions may not hold for other systems so should be reassessed for all high-quality data sets. The planet radius we measure in the g band is anomalously low and should be investigated with future observations at a higher spectral resolution. From the measured times of transit, we determine an improved orbital ephemeris, calculate a lower limit on the modified stellar tidal quality factor of |$Q_\star ^{\, \prime } \gt 10^{5.6}$|⁠, and rule out a previously postulated sinusoidal variation in the transit times. [ABSTRACT FROM AUTHOR]

We report a detection of thermal emission from the hot Jupiter WASP-48b in the Ks-band. We used the Wide-field Infra-red Camera on the 3.6-m Canada-France Hawaii Telescope to observe an occultation of the planet by its host star. From the resulting occultation lightcurve we find a planet-to-star contrast ratio in the Ks-band of 0.136 ± 0.014%, in agreement with the value of 0.109 ± 0.027% previously determined. We fit the two Ks-band occultation lightcurves simultaneously with occultation lightcurves in the H-band and the Spitzer 3.6- and 4.5-μm bandpasses, radial velocity data, and transit lightcurves. From this, we revise the system parameters and construct the spectral energy distribution (SED) of the dayside atmosphere. By comparing the SED with atmospheric models, we find that both models with and without a thermal inversion are consistent with the data. We find the planet’s orbit to be consistent with circular (e < 0.072 at 3σ). [ABSTRACT FROM AUTHOR]

We present 16 occultation and three transit light curves for the ultra-short period hot Jupiter WASP-103b, in addition to five new radial velocity measurements. We combine these observations with archival data and perform a global analysis of the resulting extensive data set, accounting for the contamination from a nearby star. We detect the thermal emission of the planet in both the ɀ' and KS bands, the measured occultation depths being 699±110 ppm (6.4σ) and 3567+400--350 ppm (10.2σ), respectively.We use these two measurements, together with recently published HST/WFC3 data, to derive joint constraints on the properties of WASP- 103b's dayside atmosphere. On one hand, we find that the ɀ' band and WFC3 data are best fit by an isothermal atmosphere at 2900K or an atmosphere with a low H2O abundance. On the other hand, we find an unexpected excess in the KS band measured flux compared to these models, which requires confirmation with additional observations before any interpretation can be given. From our global data analysis, we also derive a broad-band optical transmission spectrum that shows a minimum around 700 nm and increasing values towards both shorter and longer wavelengths. This is in agreement with a previous study based on a large fraction of the archival transit light curves used in our analysis. The unusual profile of this transmission spectrum is poorly matched by theoretical spectra and is not confirmed by more recent observations at higher spectral resolution. Additional data, in both emission and transmission, are required to better constrain the atmospheric properties of WASP-103b. [ABSTRACT FROM AUTHOR]

This paper explores the effect of Energetically Modified Fly Ash (EFA) on the durability properties of the EFA blended cement mortar. The mechanical, as well as durability properties of the EFA blended mortar, were studied. Mechanical properties were studied with the help of Compressive strength test results. Durability properties were analyzed by conducting Water Absorption Test, Sorptivity Test and Rapid Chloride Penetration Test (RCPT). Class C fly ash was used as Raw Fly Ash and Grinding of Raw fly ash in the ball mills was carried out for 2 hours to obtain Energetically Modified Fly Ash (EFA). The Ordinary Portland cement (OPC) was supplanted at 30% and 50% rates with EFA respectively. The water binding ratio's taken for mix combinations with and without 1% superplasticizers were 0.4 and 0.55 respectively. Supplanting with Energetically Modified Fly Ash at 50% rate while adopting higher w/b ratio reduced the compressive strength at 28 days age. Nevertheless, implementation of lower water to binder ratio with the help of superplasticizer would augment the durability properties of the pastes. The water absorption content diminishes with the proliferation of EFA content in the cement paste as finer EFA particles lead to a declination in permeable voids. Incorporation of EFA reduced the sorptivity values of cement paste to its "negligible" range ascribable to the reduction in pore space. The EFA specimens produced better opposition to chloride ion penetration compared to control paste. SEM analysis reveals that incorporating EFA in the mortar escalates the development of C-S-H gel by utilizing the C-H content, leading to better mechanical and durable mortar. As a consequence, it is conceivable to manufacture concrete of abridged permeability through incorporating up to 50% fly ash without undermining its strength. [ABSTRACT FROM AUTHOR]