A range of model biochemical components, microalgae and cyanobacteria with different biochemical contents have been liquefied under hydrothermal conditions at 350
°C, ∼200
bar in water, 1
M Na
2CO
3 ...and 1
M formic acid. The model compounds include albumin and a soya protein, starch and glucose, the triglyceride from sunflower oil and two amino acids. Microalgae include
Chlorella vulgaris,
Nannochloropsis occulata and
Porphyridium cruentum and the cyanobacteria
Spirulina. The yields and product distribution obtained for each model compound have been used to predict the behaviour of microalgae with different biochemical composition and have been validated using microalgae and cyanobacteria. Broad agreement is reached between predictive yields and actual yields for the microalgae based on their biochemical composition. The yields of bio-crude are 5–25
wt.% higher than the lipid content of the algae depending upon biochemical composition. The yields of bio-crude follow the trend lipids
>
proteins
>
carbohydrates.
Objective: Our objective was to evaluate the published literature and reach a consensus on the treatment of patients with ACTH-dependent Cushing’s syndrome, because there is no recent consensus on ...the management of this rare disorder.
Participants: Thirty-two leading endocrinologists, clinicians, and neurosurgeons with specific expertise in the management of ACTH-dependent Cushing’s syndrome representing nine countries were chosen to address 1) criteria for cure and remission of this disorder, 2) surgical treatment of Cushing’s disease, 3) therapeutic options in the event of persistent disease after transsphenoidal surgery, 4) medical therapy of Cushing’s disease, and 5) management of ectopic ACTH syndrome, Nelson’s syndrome, and special patient populations.
Evidence: Participants presented published scientific data, which formed the basis of the recommendations. Opinion shared by a majority of experts was used where strong evidence was lacking.
Consensus Process: Participants met for 2 d, during which there were four chaired sessions of presentations, followed by general discussion where a consensus was reached. The consensus statement was prepared by a steering committee and was then reviewed by all authors, with suggestions incorporated if agreed upon by the majority.
Conclusions: ACTH-dependent Cushing’s syndrome is a heterogeneous disorder requiring a multidisciplinary and individualized approach to patient management. Generally, the treatment of choice for ACTH-dependent Cushing’s syndrome is curative surgery with selective pituitary or ectopic corticotroph tumor resection. Second-line treatments include more radical surgery, radiation therapy (for Cushing’s disease), medical therapy, and bilateral adrenalectomy. Because of the significant morbidity of Cushing’s syndrome, early diagnosis and prompt therapy are warranted.
► The use of heterogeneous catalysts during HTL of microalgae results in increased de-oxygenation. ► Triglycerides decompose to fatty acids and are hydrogenated under hydrothermal conditions. ► The ...use of a Ni/Al2O3 catalyst de-oxygenates the lipids to form alkanes and promotes gasification.
Hydrothermal processing of high lipid feedstock such as microalgae is an alternative method of oil extraction which has obvious benefits for high moisture containing biomass. A range of microalgae and lipids extracted from terrestrial oil seed have been processed at 350°C, at pressures of 150–200bar in water. Hydrothermal liquefaction is shown to convert the triglycerides to fatty acids and alkanes in the presence of certain heterogeneous catalysts. This investigation has compared the composition of lipids and free fatty acids from solvent extraction to those from hydrothermal processing. The initial decomposition products include free fatty acids and glycerol, and the potential for de-oxygenation using heterogeneous catalysts has been investigated. The results indicate that the bio-crude yields from the liquefaction of microalgae were increased slightly with the use of heterogeneous catalysts but the higher heating value (HHV) and the level of de-oxygenation increased, by up to 10%.
Context: There is currently no medical therapy for Cushing’s disease that targets the pituitary adenoma. Availability of such a medical therapy would be a valuable therapeutic option for the ...management of this disorder.
Objective: Our objective was to evaluate the short-term efficacy of the novel multireceptor ligand somatostatin analog pasireotide in patients with de novo, persistent, or recurrent Cushing’s disease.
Design: We conducted a phase II, proof-of-concept, open-label, single-arm, 15-d multicenter study.
Patients: Thirty-nine patients with either de novo Cushing’s disease who were candidates for pituitary surgery or with persistent or recurrent Cushing’s disease after surgery without having received prior pituitary irradiation.
Intervention: Patients self-administered sc pasireotide 600 μg twice daily for 15 d.
Main Outcome Measure: Normalization of urinary free cortisol (UFC) levels after 15 d treatment was the main outcome measure.
Results: Of the 29 patients in the primary efficacy analysis, 22 (76%) showed a reduction in UFC levels, of whom five (17%) had normal UFC levels (responders), after 15 d of treatment with pasireotide. Serum cortisol levels and plasma ACTH levels were also reduced. Steady-state plasma concentrations of pasireotide were achieved within 5 d of treatment. Responders appeared to have higher pasireotide exposure than nonresponders.
Conclusions: Pasireotide produced a decrease in UFC levels in 76% of patients with Cushing’s disease during the treatment period of 15 d, with direct effects on ACTH release. These results suggest that pasireotide holds promise as an effective medical treatment for this disorder.
Results from this phase II study show pasireotide to be a promising pituitary-directed medical therapy for patients with Cushing’s disease.
Aquatic organisms such as microalgae have been identified as a potential source of third generation biofuels due to their fast growth rate, ability to sequester CO
2 and their potential for producing ...lipids. Conversion by hydrothermal liquefaction is ideally suited to high moisture content feedstocks such as microalgae and involves the processing of biomass in hot compressed water with or without the presence of a catalyst. This study aims to investigate the conditions for producing high quality, low molecular weight bio-crude from microalgae and cyanobacteria containing low lipid contents including
Chlorella vulgaris and
Spirulina. Liquefaction experiments have been performed in a high pressure batch reactor at 300
°C and 350
°C. The influence of process variables such as temperature and catalyst type has been studied. Catalysts employed include the alkali, potassium hydroxide and sodium carbonate and the organic acids, acetic acid and formic acid. Liquefaction yields have been determined and the bio-crude has been analysed for CHNOS content and calorific value. The bio-crude has been analysed by GC/MS to examine composition and thermal gravimetric analysis (TGA) to estimate its boiling point range. The aqueous fraction has been analysed for typical cations and anions by ion exchange chromatography and for total organic carbon (TOC). The yields of bio-crude are higher using an organic acid catalyst, have a lower boiling point and improved flow properties. The bio-crude contains a carbon content of typically 70–75% and an oxygen content of 10–16%. The nitrogen content in the bio-crude typically ranges from 4% to 6%. The higher heating values (HHV) range from 33.4 to 39.9
MJ
kg
−1. Analysis by GC/MS indicates that the bio-crude contains aromatic hydrocarbons, nitrogen heterocycles and long chain fatty acids and alcohols. A nitrogen balance indicates that a large proportion of the fuel nitrogen (up to 50%) is transferred to the aqueous phase in the form of ammonium. The remainder is distributed between the bio-crude and the gaseous phase the latter containing HCN, NH
3 and N
2O depending upon catalyst conditions. The addition of organic acids results in a reduction of nitrogen in the aqueous phase and a corresponding increase of NH
3 and HCN in the gas phase. The addition of organic acids has a beneficial effect on the yield and boiling point distribution of the bio-crude produced.
Context.
Detecting and characterizing substellar companions for which the luminosity, mass, and age can be determined independently is of utter importance to test and calibrate the evolutionary ...models due to uncertainties in their formation mechanisms. HD 19467 is a bright and nearby star hosting a cool brown dwarf companion detected with radial velocities and imaging, making it a valuable object for such studies.
Aims.
We aim to further characterize the orbital, spectral, and physical properties of the HD 19467 system.
Methods.
We present new high-contrast imaging data with the SPHERE and NaCo instruments. We also analyze archival data from the instruments HARPS, NaCo, HIRES, UVES, and ASAS. Furthermore, we use proper motion data of the star from H
IPPARCOS
and
Gaia
.
Results.
We refined the properties of the host star and derived an age of 8.0
+2.0
−1.0
Gyr based on isochrones, gyrochronology, and chemical and kinematic arguments. This age estimate is slightly younger than previous age estimates of ~9–11 Gyr based on isochrones. No orbital curvature is seen in the current imaging, radial velocity, and astrometric data. From a joint fit of the data, we refined the orbital parameters for HD 19467B, including: a period of 398
+95
−93
yr, an inclination of 129.8
+8.1
−5.1
deg, an eccentricity of 0.56 ± 0.09, a longitude of the ascending node of 134.8 ± 4.5 deg, and an argument of the periastron of 64.2
+5.5
−6.3
deg. We assess a dynamical mass of 74
+12
−9
M
J
. The fit with atmospheric models of the spectrophotometric data of the companion indicates an atmosphere without clouds or with very thin clouds, an effective temperature of 1042
+77
−71
K, and a high surface gravity of 5.34
+0.8
−0.9
dex. The comparison to model predictions of the bolometric luminosity and dynamical mass of HD 19467B, assuming our system age estimate, indicates a better agreement with the Burrows et al. (1997, ApJ, 491, 856) models; whereas, the other evolutionary models used tend to underestimate its cooling rate.
In a previous 15-day, Phase II study of patients with de novo or persistent/recurrent Cushing’s disease (core study), treatment with pasireotide 600 μg sc bid reduced urinary free cortisol (UFC) ...levels in 76 % of patients and normalized UFC in 17 %. The objective of this study was to evaluate the efficacy and safety of extended treatment with pasireotide. This was a planned, open-ended, single-arm, multicenter extension study (primary endpoint: 6 months). Patients aged ≥18 years with Cushing’s disease who completed the core study could enter the extension if they achieved UFC normalization at core study end and/or obtained significant clinical benefit. Of the 38 patients who completed the core study, 19 entered the extension and 18 were included in the efficacy analyses (three responders, 11 reducers, four non-reducers in the core study). At data cut-off, median treatment duration in the extension was 9.7 months (range: 2 months to 4.8 years). At extension month 6, 56 % of the 18 patients had lower UFC than at core baseline and 22 % had normalized UFC. Of the four patients who remained on study drug at month 24, one had normalized UFC. Reductions in serum cortisol, plasma adrenocorticotropic hormone, body weight and diastolic blood pressure were observed. The most common adverse events were mild-to-moderate gastrointestinal disorders and hyperglycemia. Pasireotide offers a tumor-directed medical therapy that may be effective for the extended treatment of some patients with Cushing’s disease.
Tests on B−L symmetry breaking models are important probes to search for new physics. One proposed model with Δ(B−L)=2 involves the oscillations of a neutron to an antineutron. In this paper, a new ...limit on this process is derived for the data acquired from all three operational phases of the Sudbury Neutrino Observatory experiment. The search concentrated on oscillations occurring within the deuteron, and 23 events were observed against a background expectation of 30.5 events. These translated to a lower limit on the nuclear lifetime of 1.48×1031 yr at 90% C.L. when no restriction was placed on the signal likelihood space (unbounded). Alternatively, a lower limit on the nuclear lifetime was found to be 1.18×1031 yr at 90% C.L. when the signal was forced into a positive likelihood space (bounded). Values for the free oscillation time derived from various models are also provided in this article. This is the first search for neutron-antineutron oscillation with the deuteron as a target.
Aims.
The rotational spectral modulation (spectro-photometric variability) of brown dwarfs is usually interpreted as a sign indicating the presence of inhomogeneous cloud covers in the atmosphere. ...This paper is aimed at exploring the role of temperature fluctuations in these spectral modulations. These fluctuations could naturally arise in a convective atmosphere impacted by such diabatic processes as complex chemistry, namely, a mechanism recently proposed to explain the L/T transition: CO/CH
4
radiative convection.
Methods.
After exploring the observed spectral-flux ratios between different objects along the cooling sequence, we used the 1D radiative-convective code
ATMO,
with ad hoc modifications of the temperature gradient, to model the rotational spectral modulation of 2MASS 1821, 2MASS 0136, and PSO 318.5-22. We also explored the impact of CH
4
abundance fluctuations on the spectral modulation of 2MASS 0136.
Results.
The spectral-flux ratio of different objects along the cooling sequence and the rotational spectral modulation within individual objects at the L/T transition have similar characteristics. This strongly suggests that the main parameter varying along the cooling sequence, namely, temperature, might play a key role in the rotational spectral modulations at the L/T transition. Modeling the spectral bright-to-faint ratio of the modulation of 2MASS 1821, 2MASS 0136, and PSO 318.5-22 shows that most spectral characteristics can be reproduced by temperature variations alone. Furthermore, the approximately anti-correlated variability between different wavelengths can be easily interpreted as a change in the temperature gradient in the atmosphere, which is a consequence we expect from CO/CH
4
radiative convection as an explanation of the L/T transition. The deviation from an exact anti-correlation could then be interpreted as a phase shift similar to the hot-spot shift at different bandpasses in the atmospheres of hot Jupiters.
Conclusions.
Our results suggest that the rotational spectral modulation from cloud opacity and temperature variations are degenerate. If the nearly anti-correlated signal between different wavelengths is, indeed, a strong sign of a change in the temperature gradient, the detection of direct cloud spectral signatures, for instance, the silicate absorption feature at 10
μ
m, would help to confirm the presence of clouds and their contribution to spectral modulations (which does not exclude temperature variations or other mechanisms that may also be at play). Future studies considering the differences in the spectral modulation of objects with and without the silicate absorption feature may give us some insight into how to distinguish cloud-opacity fluctuations from temperature fluctuations.
We examine the implications for the distribution of extrasolar planets based on the null results from two of the largest direct imaging surveys published to date. Combining the measured contrast ...curves from 22 of the stars observed with the VLT NACO adaptive optics system by Mascladrl and coworkers and 48 of the stars observed with the VLT NACO SDI and MMT SDI devices by Biller and coworkers (for a total of 60 unique stars), we consider what distributions of planet masses and semimajor axes can be ruled out by these data, based on Monte Carlo simulations of planet populations. We can set the following upper limit with 95% confidence: the fraction of stars with planets with semfmajor axis between 20 and 100 AU, and mass above 4 M sub(Jup), is 20% or less. Also, with a distribution of planet mass of dN/dM proportional to M super(-1.16) in the range of 0.5-13 M sub(Jup), we can rule out a power-law distribution for semimajor axis (dN/da proportional to a super(0)) with index 0 and upper cutoff of 18 AU, and index -0.5 with an upper cutoff of 48 AU. For the distribution suggested by Cumming et al., a power-law of index -0.61, we can place an upper limit of 75 AU on the semimajor axis distribution. In general, we find that even null results from direct imaging surveys are very powerful in constraining the distributions of giant planets (0.5-13 M sub(Jup)) at large separations, but more work needs to be done to close the gap between planets that can be detected by direct imaging, and those to which the radial velocity method is sensitive.
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