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© 2017. The American Astronomical Society. All rights reserved. Detecting the atmospheres of low-mass, low-temperature exoplanets is a high-priority goal on the path to ultimately detecting biosignatures in the atmospheres of habitable exoplanets. High-precision HST observations of several super-Earths with equilibrium temperatures below 1000 K have to date all resulted in featureless transmission spectra, which have been suggested to be due to high-altitude clouds. We report the detection of an atmospheric feature in the atmosphere of a 1.6 M⊕ transiting exoplanet, GJ 1132 b, with an equilibrium temperature of ∼600 K and orbiting a nearby M dwarf. We present observations of nine transits of the planet obtained simultaneously in the griz and JHK passbands. We find an average radius of 1.43 ±0.16 R⊕ for the planet, averaged over all the passbands, and a radius of 0.255 ±0.023 R⊙for the star, both of which are significantly greater than previously found. The planet radius can be decomposed into a "surface radius" at ∼1.375 R⊕ overlaid by atmospheric features that increase the observed radius in the z and K bands. The z-band radius is 4σ higher than the continuum, suggesting a strong detection of an atmosphere. We deploy a suite of tests to verify the reliability of the transmission spectrum, which are greatly helped by the existence of repeat observations. The large z-band transit depth indicates strong opacity from H2O and/or CH4 or a hitherto-unconsidered opacity. A surface radius of 1.375 ±0.16 R⊕ allows for a wide range of interior compositions ranging from a nearly Earth-like rocky interior, with ∼70% silicate and ∼30% Fe, to a substantially H2O-rich water world.

We present a high precision H-band emission spectrum of the transiting brown dwarf KELT-1b, which we spectrophotometrically observed during a single secondary eclipse using the LUCI1 multi-object spectrograph on the Large Binocular Telescope. Using a Gaussian-process regression model, we are able to clearly measure the broadband eclipse depth as Delta-H=1418+/-94ppm. We are also able to spectrally-resolve the H-band into five separate wavechannels and measure the eclipse spectrum of KELT-1b at R~50 with an average precision of +/-135ppm. We find that the day side has an average brightness temperature of 3250+/-50K, with significant variation as a function of wavelength. Based on our observations, and previous measurements of KELT-1b's eclipse at other wavelengths, we find that KELT-1b's day side appears identical to an isolated 3200K brown dwarf, and our modeling of the atmospheric emission shows a monotonically decreasing temperature-pressure profile. This is in contrast to hot Jupiters with similar day side brightness temperatures near 3000K, all of which appear to be either isothermal or posses a stratospheric temperature inversion. We hypothesize that the lack of an inversion in KELT-1b is due to its high surface gravity, which we argue could be caused by the increased efficiency of cold-trap processes within its atmosphere.

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).

The James Webb Space Telescope (JWST) presents the opportunity to transform our understanding of planets and the origins of life by revealing the atmospheric compositions, structures, and dynamics of transiting exoplanets in unprecedented detail. However, the high-precision, time-series observations required for such investigations have unique technical challenges, and prior experience with other facilities indicates that there will be a steep learning curve when JWST becomes operational. In this paper we describe the science objectives and detailed plans of the Transiting Exoplanet Community Early Release Science (ERS) Program, which is a recently approved program for JWST observations early in Cycle 1. The goal of this project, for which the obtained data will have no exclusive access period, is to accelerate the acquisition and diffusion of technical expertise for transiting exoplanet observations with JWST, while also providing a compelling set of representative datasets that will enable immediate scientific breakthroughs. The Transiting Exoplanet Community ERS Program will exercise the time-series modes of all four JWST instruments that have been identified as the consensus highest priorities, observe the full suite of transiting planet characterization geometries (transits, eclipses, and phase curves), and target planets with host stars that span an illustrative range of brightnesses. The observations in this program were defined through an inclusive and transparent process that had participation from JWST instrument experts and international leaders in transiting exoplanet studies. Community engagement in the project will be centered on a two-phase Data Challenge that culminates with the delivery of planetary spectra, time-series instrument performance reports, and open-source data analysis toolkits in time to inform the agenda for Cycle 2 of the JWST mission.

© 2017 The Author(s). 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 z' and KS bands, the measured occultation depths being 699±110 ppm (6.4σ) and 3567 -350 +400 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 z' band and WFC3 data are best fit by an isothermal atmosphere at 2900K or an atmosphere with a low H 2 O abundance. On the other hand, we find an unexpected excess in the K S 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.

© 2017. The American Astronomical Society. All rights reserved. Detecting the atmospheres of low-mass, low-temperature exoplanets is a high-priority goal on the path to ultimately detecting biosignatures in the atmospheres of habitable exoplanets. High-precision HST observations of several super-Earths with equilibrium temperatures below 1000 K have to date all resulted in featureless transmission spectra, which have been suggested to be due to high-altitude clouds. We report the detection of an atmospheric feature in the atmosphere of a 1.6 M⊕ transiting exoplanet, GJ 1132 b, with an equilibrium temperature of ∼600 K and orbiting a nearby M dwarf. We present observations of nine transits of the planet obtained simultaneously in the griz and JHK passbands. We find an average radius of 1.43 ±0.16 R⊕ for the planet, averaged over all the passbands, and a radius of 0.255 ±0.023 R⊙for the star, both of which are significantly greater than previously found. The planet radius can be decomposed into a "surface radius" at ∼1.375 R⊕ overlaid by atmospheric features that increase the observed radius in the z and K bands. The z-band radius is 4σ higher than the continuum, suggesting a strong detection of an atmosphere. We deploy a suite of tests to verify the reliability of the transmission spectrum, which are greatly helped by the existence of repeat observations. The large z-band transit depth indicates strong opacity from H2O and/or CH4 or a hitherto-unconsidered opacity. A surface radius of 1.375 ±0.16 R⊕ allows for a wide range of interior compositions ranging from a nearly Earth-like rocky interior, with ∼70% silicate and ∼30% Fe, to a substantially H2O-rich water world.

BACKGROUND AND OBJECTIVES: Cryptococcal meningitis is an important cause of mortality among HIV infected patients. A prospective study consisting of 106 HIV seropositive patients was undertaken to know the incidence of Cryptococcal meningitis, to correlate with CD4 count, to analyze the distribution of demographic factors like age, sex and symptoms and biochemical and cytological changes in cerebrospinal fluid. METHODS: CSF samples from HIV seropositive patients with suspected meningitis were subjected to Cytological and biochemical analysis. Latex agglutination test for antigen detection (LAT). CD4 cell count estimated by Flow cytometry. RESULTS: LAT was positive in 29(27.36%) patients. The incidence was highest (38.7%) in patients with CD4 count

Mycobacterium tuberculosis enoyl-ACP reductase (InhA) has been validated as a promising target for antitubercular agents. Isoniazid (INH), the most prescribed drug to treat tuberculosis (TB), inhibits a NADH-dependent InhA that provides precursors of mycolic acids, which are components of the mycobacterial cell wall. It is a pro-drug that needs activation to form the inhibitory INH-NAD adduct by KatG coding for catalase-peroxidase. The INH resistance of M. tuberculosis is caused by mutations in KatG, which may lead to multidrug-resistant TB (MDR-TB). Hence, there is a need for new drugs that can combat MDR-TB. The rationale for the development of new drugs to combat MDR-TB strains is the design of InhA inhibitors that can bypass bioactivation by KatG. In the present review, special attention was paid to discuss the chemical nature and recent developments of direct InhA inhibitors. The InhA inhibitors reported here have significant inhibitory effects against Mtb InhA. The diphenyl ether derivatives have shown slow onset, a tight-binding mechanism, and high affinity at the InhA active site. However, some of the diphenyl ethers have significant in vitro efficacy, which fails to transform into in vivo efficacy. Among the InhA inhibitors, 4-hydroxy-2-pyridones have emerged as a new chemical class with significant InhA inhibitory activity and better pharmacokinetic parameters when compared to diphenyl ethers.

Hydroxyzine is the first generation H1 receptor antagonist drug that is now marketed as a racemic mixture. The paper describes a validated enantioselective liquid chromatography method for the resolution of hydroxyzine enantiomers and cyclizine (internal standard) from 200 µL of rabbit plasma by liquid-liquid extraction technique using n-hexane and isopropanol. Hydroxyzine enantiomers were resolved at 10.2 and 11.1 min with good baseline resolution (Rs = 1.9) on a Lux amylose-2 chiral column (250 mm × 4.0 mm, 5 microns) at ambient room temperature. The mobile phase consisted of n-hexane-ethanol-diethylamine (90:10:0.1 v/v/v) pumped at 0.9 mL/min. The eluted enantiomers were detected at 254 nm. The linear calibration curve was constructed in the range 20-1000 ng/mL for both the (S)- and (R)-enantiomers. The intra- and inter-day precision were 0.16-2.6% and 0.2-1.92% for (S)-hydroxyzine and (R)-hydroxyzine, respectively. The method was successfully applied to determine the kinetic parameters of (S)- and (R)-hydroxyzine enantiomers in rabbits. The results illustrate that the disposition of hydroxyzine enantiomers is not stereoselective in rabbits.

Background: Enteric fever is classically caused by Salmonella enterica serotype Typhi. There has been increase in enteric fever cases from different parts of India caused by Salmonella enterica serotype Paratyphi A. Thereby a retrospective study was conducted to determine the rate of isolation and antimicrobial susceptibility pattern of Salmonella Paratyphi A in comparison to Salmonella Typhi. Methods: A retrospective analysis of laboratory records was carried out from January 2011-December 2014. Conventional blood culture method was used. Salmonella were confirmed by serotyping using group and type specific anti-sera. Antibiotic susceptibility was performed for ampicillin, cotrimoxazole, ciprofloxacin, chloramphenicol and ceftriaxone, using Kirby Bauers disk diffusion method. Results: Out of 258 Salmonella isolates, 127 (49.2 %) were Salmonella Typhi and 131 (50.8 %) were Salmonella Paratyphi A. Salmonella Paratyphi A cases increased from 23.4% in 2011-2013 to 91.3% in 2014. Salmonella Typhi were 98.4 % sensitive to ampicillin and ceftriaxone and 99.2% sensitive to chloramphenicol and cotrimoxazole. Only 29.9% were sensitive to ciprofloxacin. Similarly, Salmonella Paratyphi A isolates were 99.2 % sensitive to ampicillin and 100 % sensitive to cotrimoxazole and ceftriaxone and 96.9 % sensitive to chloramphenicol and only 14.5 % sensitive to ciprofloxacin.Conclusion: The present study confers Salmonella Paratyphi A as the rapidly emerging pathogen of enteric fever. The antibiogram of Salmonella Typhi and Salmonella Paratyphi A showed decreased susceptibility to fluoroquinolones and a notable decrease in the multi drug resistant strains of Salmonella isolates with re-emergence of susceptibility to first line antibiotics.

Mycobacterium tuberculosis enoyl-ACP reductase (InhA) has been validated as a promising target for antitubercular agents. Isoniazid (INH), the most prescribed drug to treat tuberculosis (TB), inhibits a NADH-dependent InhA that provides precursors of mycolic acids, which are components of the mycobacterial cell wall. It is a pro-drug that needs activation to form the inhibitory INH-NAD adduct by KatG coding for catalase-peroxidase. The INH resistance of M. tuberculosis is caused by mutations in KatG, which may lead to multidrug-resistant TB (MDR-TB). Hence, there is a need for new drugs that can combat MDR-TB. The rationale for the development of new drugs to combat MDR-TB strains is the design of InhA inhibitors that can bypass bioactivation by KatG. In the present review, special attention was paid to discuss the chemical nature and recent developments of direct InhA inhibitors. The InhA inhibitors reported here have significant inhibitory effects against Mtb InhA. The diphenyl ether derivatives have shown slow onset, a tight-binding mechanism, and high affinity at the InhA active site. However, some of the diphenyl ethers have significant in vitro efficacy, which fails to transform into in vivo efficacy. Among the InhA inhibitors, 4-hydroxy-2-pyridones have emerged as a new chemical class with significant InhA inhibitory activity and better pharmacokinetic parameters when compared to diphenyl ethers.

Pd-mediated cycloisomerization of 3-C-alkynyl-allo- and ribofuranose derivatives was investigated in detail to understand the influence of electronic factors on the regioselectivity in ring closure reaction. The reactions in general are influenced by the electronic nature of the substituent on the alkyne unit. A preference for endo-dig cyclization over exo-dig is noted, if the alkynyl substituent is not sufficiently electron withdrawing.

With the purpose of designing novel chemical entities with improved inhibitory potencies against drug-resistant Mycobacterium tuberculosis, the 3D- quantitative structure-activity relationship (QSAR) studies were carried out on biphenyl analogs of the tuberculosis (TB) drug, PA-824. Anti-mycobacterial activity (MABA) was considered for the 3D-QSAR studies using the comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) approaches. The best CoMFA and CoMSIA models were found statistically significant with cross-validated coefficients (q(2)) of 0.784 and 0.768, respectively, and conventional coefficients (r(2)) of 0.823 and 0.981, respectively. The cross-validated and the external validation results revealed that both the CoMFA and CoMSIA models possesses high accommodating capacities and they would be reliable for predicting the pMIC values of new PA-824 derivatives. Based on the models and structural insights, a series of new PA-824 derivatives were designed and the anti-mycobacterial activities of the designed compounds were predicted based on the best 3D-QSAR model. The predicted data results suggest the designed compounds are more potent than existed ones.

Aims. We observe occultations of WASP-24b to measure brightness temperatures and to determine whether or not its atmosphere exhibits a thermal inversion (stratosphere). Methods. We observed occultations of WASP-24b at 3.6 and 4.5 ��m using the Spitzer Space Telescope. It has been suggested that there is a correlation between stellar activity and the presence of inversions, so we analysed existing HARPS spectra in order to calculate log R'HK for WASP-24 and thus determine whether or not the star is chromospherically active. We also observed a transit of WASP-24b in the Str��mgren u and y bands, with the CAHA 2.2-m telescope. Results. We measure occultation depths of 0.159 \pm 0.013 per cent at 3.6 ��m and 0.202 \pm 0.018 per cent at 4.5 ��m. The corresponding planetary brightness temperatures are 1974 \pm 71 K and 1944 \pm 85 K respectively. Atmosphere models with and without a thermal inversion fit the data equally well; we are unable to constrain the presence of an inversion without additional occultation measurements in the near-IR. We find log R'HK = -4.98 \pm 0.12, indicating that WASP-24 is not a chromospherically active star. Our global analysis of new and previously-published data has refined the system parameters, and we find no evidence that the orbit of WASP-24b is non-circular. Conclusions. These results emphasise the importance of complementing Spitzer measurements with observations at shorter wavelengths to gain a full understanding of hot Jupiter atmospheres., 7 pages, 4 figures, 3 tables. Accepted for publication in A&A

We present here the results of our observations of TrES-2 using the Infrared Array Camera on Spitzer. We monitored this transiting system during two secondary eclipses, when the planetary emission is blocked by the star. The resulting decrease in flux is 0.127% ± 0.021%, 0.230% ± 0.024%, 0.199% ± 0.054%, and 0.359% ± 0.060% at 3.6 μm, 4.5 μm, 5.8 μm, and 8.0 μm, respectively. We show that three of these flux contrasts are well fit by a blackbody spectrum with T_(eff) = 1500 K, as well as by a more detailed model spectrum of a planetary atmosphere. The observed planet-to-star flux ratios in all four IRAC channels can be explained by models with and without a thermal inversion in the atmosphere of TrES-2, although with different atmospheric chemistry. Based on the assumption of thermochemical equilibrium, the chemical composition of the inversion model seems more plausible, making it a more favorable scenario. TrES-2 also falls in the category of highly irradiated planets which have been theoretically predicted to exhibit thermal inversions. However, more observations at infrared and visible wavelengths would be needed to confirm a thermal inversion in this system. Furthermore, we find that the times of the secondary eclipses are consistent with previously published times of transit and the expectation from a circular orbit. This implies that TrES-2 most likely has a circular orbit, and thus does not obtain additional thermal energy from tidal dissipation of a non-zero orbital eccentricity, a proposed explanation for the large radius of this planet.

Two stereocontrolled approaches towards a precursor of 1 β-methylthienamycin, have been accomplished by involving stereospecific hydrogenation of 13 and stereoselective hydroboration oxidation of 9. The latter compounds were obtained from the easily accessible chiral building block 7. The hydroboration-oxidation approach was extended to 18 in which the optically active 1R- (1-hydroxy ethyl) side-chain was incorporated. The highly stereoselective hydroboration-oxidation reaction of 9 is explained by considering Houk's models.

We investigate the evolution of the properties of model populations of ultraluminous X-ray sources (ULXs) consisting of a black-hole accretor in a binary with a donor star. We have computed models corresponding to two different. populations of black-hole binaries: one invokes stellar-mass (similar to 10 M-circle dot) black hole accretors(1) (LMBHs), and the second utilizes intermediate-mass (similar to 1000M(circle dot)) black holes (IMBHs). For each of the two populations, we computed 30,000 binary evolution sequences using a full Henyey stellar evolution code. The optical flux from the model ULXs includes contributions from the donor star and the accretion disk (the latter being due to X-ray irradiation as well as intrinsic viscous heating). We present. "probability images" for the ULX systems in planes of color-magnitude, orbital period vs. X-ray luminosity, and luminosity vs. evolution time. Estimates of the numbers of ULXs in a typical galaxy as a function of X-ray luminosity are also presented. Our model CMDs are compared with six ULX counterparts that have been discussed in the literature. Overall, the observed systems seem more closely related to model systems with very high-mass donors (greater than or similar to 25 M-circle dot) in binaries with IMBH accretors. However, significant difficulties remain with both the IMBH and stellar-mass black hole models.