Organic Material on Ceres: Insights from Visible and Infrared Space Observations

The NASA/Dawn mission has acquired unprecedented measurements of the surface of the dwarf planet Ceres, the composition of which is a mixture of ultra-carbonaceous material, phyllosilicates, carbonates, organics, Fe-oxides, and volatiles as determined by remote sensing instruments including the VIR imaging spectrometer. We performed a refined analysis merging visible and infrared observations of Ceres’ surface for the first time. The overall shape of the combined spectrum suggests another type of silicate not previously considered, and we confirmed a large abundance of carbon material. More importantly, by analyzing the local spectra of the organic-rich region of the Ernutet crater, we identified a reddening in the visible range, strongly correlated to the aliphatic signature at 3.4 µm. Similar reddening was found in the bright material making up Cerealia Facula in the Occator crater. This implies that organic material might be present in the source of the faculae, where brines and organics are mixed in an environment that may be favorable for prebiotic chemistry.

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DLR HySU—A Benchmark Dataset for Spectral Unmixing

Remote Sensing ◽

10.3390/rs13132559 ◽

2021 ◽

Vol 13 (13) ◽

pp. 2559

Author(s):

Daniele Cerra ◽

Miguel Pato ◽

Kevin Alonso ◽

Claas Köhler ◽

Mathias Schneider ◽

...

Keyword(s):

Spectral Unmixing ◽

Benchmark Dataset ◽

Data Sets ◽

Endmember Extraction ◽

Imaging Spectrometer ◽

Hyperspectral Unmixing ◽

Processing Step ◽

German Aerospace ◽

Spectrometer Data ◽

First Time

Spectral unmixing represents both an application per se and a pre-processing step for several applications involving data acquired by imaging spectrometers. However, there is still a lack of publicly available reference data sets suitable for the validation and comparison of different spectral unmixing methods. In this paper, we introduce the DLR HyperSpectral Unmixing (DLR HySU) benchmark dataset, acquired over German Aerospace Center (DLR) premises in Oberpfaffenhofen. The dataset includes airborne hyperspectral and RGB imagery of targets of different materials and sizes, complemented by simultaneous ground-based reflectance measurements. The DLR HySU benchmark allows a separate assessment of all spectral unmixing main steps: dimensionality estimation, endmember extraction (with and without pure pixel assumption), and abundance estimation. Results obtained with traditional algorithms for each of these steps are reported. To the best of our knowledge, this is the first time that real imaging spectrometer data with accurately measured targets are made available for hyperspectral unmixing experiments. The DLR HySU benchmark dataset is openly available online and the community is welcome to use it for spectral unmixing and other applications.

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Delayed implantation in giant pandas: the first comprehensive empirical evidence

Reproduction ◽

10.1530/rep-09-0241 ◽

2009 ◽

Vol 138 (6) ◽

pp. 979-986 ◽

Cited By ~ 26

Author(s):

Hemin Zhang ◽

Desheng Li ◽

Chendong Wang ◽

Vanessa Hull

Keyword(s):

Reproductive Biology ◽

Giant Panda ◽

Reproductive Development ◽

Mammary Glands ◽

Strongly Correlated ◽

Physiological Changes ◽

Giant Pandas ◽

Delayed Implantation ◽

Infant Birth ◽

First Time

Successful conservation of an endangered species relies on a good understanding of its reproductive biology, but there are large knowledge gaps. For example, many questions remain unanswered with regard to gestation and fetal development in the giant panda. We take advantage of a sample size that is unprecedented for this species (n=13) to explore patterns in reproductive development across individuals at the China Conservation and Research Center for the Giant Panda. We use ultrasound techniques on multiple giant pandas for the first time to empirically confirm what has long been suspected that pandas exhibit delayed implantation of the embryo. We also show that the duration of postfetal detection period is remarkably similar across individuals (16.85±1.34 days). Detection of fetus by ultrasound was strongly correlated to the peak in urinary progesterone (r=0.96, t=8.48, d.f.=8, P=0.0001) and swelling in the mammary glands (r=0.79, t=3.61, d.f.=8, P=0.007) and vulva (r=0.91, t=6.40, d.f.=8, P=0.0002) of adult females. When controlling for both the duration of the total gestation period and the postfetal detection period, infant birth weight was only significantly predicted by the latter (β=11.25, s.e.m.=4.98, t=2.26, P=0.05), suggesting that delayed implantation increases flexibility in the timing of birth but is not important in dictating infant growth. This study informs reproductive biology by exploring the little-studied phenomenon of delayed implantation in relationship to physiological changes in pregnant giant panda females.

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Information-based analysis of the coupling between brain and heart reactions to olfactory stimulation

Technology and Health Care ◽

10.3233/thc-213136 ◽

2021 ◽

pp. 1-11

Author(s):

Najmeh Pakniyat ◽

Mohammad Hossein Babini ◽

Vladimir V. Kulish ◽

Hamidreza Namazi

Keyword(s):

Time Series ◽

Biomedical Science ◽

Strongly Correlated ◽

Eeg Signals ◽

Ecg Signals ◽

Olfactory Stimuli ◽

Electrocardiogram Ecg ◽

First Time ◽

Electroencephalogram Eeg ◽

The Brain

BACKGROUND: Analysis of the heart activity is one of the important areas of research in biomedical science and engineering. For this purpose, scientists analyze the activity of the heart in various conditions. Since the brain controls the heart’s activity, a relationship should exist among their activities. OBJECTIVE: In this research, for the first time the coupling between heart and brain activities was analyzed by information-based analysis. METHODS: Considering Shannon entropy as the indicator of the information of a system, we recorded electroencephalogram (EEG) and electrocardiogram (ECG) signals of 13 participants (7 M, 6 F, 18–22 years old) in different external stimulations (using pineapple, banana, vanilla, and lemon flavors as olfactory stimuli) and evaluated how the information of EEG signals and R-R time series (as heart rate variability (HRV)) are linked. RESULTS: The results indicate that the changes in the information of the R-R time series and EEG signals are strongly correlated (ρ=-0.9566). CONCLUSION: We conclude that heart and brain activities are related.

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Self-Dividing Micelles: A Mechanistic Look with Evolutionary and Clinical Implications

10.36811/ijbm.2021.110023 ◽

2021 ◽

pp. 8-20

Keyword(s):

Fatty Acid ◽

Amino Acid ◽

Laboratory Testing ◽

Prebiotic Chemistry ◽

Clinical Implications ◽

Proof Of Concept ◽

Mass Spec ◽

First Time ◽

Division Mechanism ◽

Viable Treatment

Micellar therapy has become a usefully viable treatment arm in various fields, ranging from oncology to bioimaging. As such, research leading to any improvements or adaptations in administration and techniques can have far-reaching consequences. Potential aspects of prebiotic chemistry may also be explored in such research as well. To that end, proof-of-concept experiments were performed to elucidate a possible mechanism of action for prebiotic protocell division. Representative potentially prebiotically plausible biomolecules, i.e., a fatty acid, amino acid, and nucleotide were mixed and heated in water and subjected to microscopic examination for observation of possible self-division and laboratory testing for the presence of polypeptides and polynucleotides (Biuret, MALDI mass-spec, etc.) with and without the presence of nucleotide. The results are presented for the first time here and a mechanism is proposed that best fits the data obtained. The evolutionary, e.g., prebiotic biomolecular cooperativity, and clinical, e.g., potential antineoplastic micellar/vesicular therapy, ramifications are discussed as well. Keywords: Micelle; Liposome; Protocell; MRNA; Self-division; Mechanism; Solid tumors

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Lidar profiling of aerosol optical properties from Paris to Lake Baikal (Siberia)

Atmospheric Chemistry and Physics ◽

10.5194/acp-15-5007-2015 ◽

2015 ◽

Vol 15 (9) ◽

pp. 5007-5026 ◽

Cited By ~ 19

Author(s):

E. Dieudonné ◽

P. Chazette ◽

F. Marnas ◽

J. Totems ◽

X. Shang

Keyword(s):

Optical Properties ◽

Lake Baikal ◽

Forest Fires ◽

Western Europe ◽

Lower Boundary ◽

Aerosol Optical Properties ◽

Imaging Spectrometer ◽

Moderate Resolution ◽

The Difference ◽

First Time

Abstract. In June 2013, a ground-based mobile lidar performed the ~10 000 km ride from Paris to Ulan-Ude, near Lake Baikal, profiling for the first time aerosol optical properties all the way from western Europe to central Siberia. The instrument was equipped with N2-Raman and depolarization channels that enabled an optical speciation of aerosols in the low and middle troposphere. The extinction-to-backscatter ratio (also called lidar ratio or LR) and particle depolarization ratio (PDR) at 355 nm have been retrieved. The LR in the lower boundary layer (300–700 m) was found to be 63 ± 17 sr on average during the campaign with a distribution slightly skewed toward higher values that peaks between 50 and 55 sr. Although the difference is small, PDR values observed in Russian cities (>2%, except after rain) are systematically higher than the ones measured in Europe (<1%), which is probably an effect of the lifting of terrigenous aerosols by traffic on roads. Biomass burning layers from grassland or/and forest fires in southern Russia exhibit LR values ranging from 65 to 107 sr and from 3 to 4% for the PDR. During the route, desert dust aerosols originating from the Caspian and Aral seas regions were characterized for the first time, with a LR (PDR) of 43 ± 14 sr (23 ± 2%) for pure dust. The lidar observations also showed that this dust event extended over 2300 km and lasted for ~6 days. Measurements from the Moderate Resolution Imaging Spectrometer (MODIS) show that our results are comparable in terms of aerosol optical thickness (between 0.05 and 0.40 at 355 nm) with the mean aerosol load encountered throughout our route.

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New Structures and Materials for Next Generation Photonic Technology

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.120.556 ◽

2011 ◽

Vol 120 ◽

pp. 556-560

Author(s):

D. H Zhang ◽

T. Mei ◽

D.Y. Tang ◽

X. C. Yuan ◽

T. P. Chen

Keyword(s):

Light Source ◽

Silicon On Insulator ◽

Visible Range ◽

Light Emitting ◽

Light Emitting Devices ◽

Light Manipulation ◽

Loss Compensation ◽

Photonic Circuit ◽

Nano Crystal ◽

First Time

We present the main results achieved in light source, light manipulation and imaging and sensing in our competitive research program. In light source, we have for the first time developed grapheme mode-locked lasers and dark pause lasers as well as nano-crystal Si based light emitting devices with colour tunable. In light manipulation, loss compensation of surface plasmon polaritons (SPPs) using semiconductor gain media was studied theoretically and demonstrated experimentally and the SPP propagation can be controlled through electrical pumping. Microring resonators based on silicon on insulator and III-V semiconductors technologies have been successfully fabricated and they can be used as filter and switch in the photonic circuit. In imaging and sensing, both SPP and metamaterial based lenses are developed and resolution far beyond diffraction limit in visible range has been realized. Broadband photodetectors based on dilute nitrides are also demonstrated.

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Mori Ramulus (Chin.Ph.)—the Dried Twigs of Morus alba L./Part 1: Discovery of Two Novel Coumarin Glycosides from the Anti-Hyperuricemic Ethanol Extract

Molecules ◽

10.3390/molecules24030629 ◽

2019 ◽

Vol 24 (3) ◽

pp. 629

Author(s):

Jianbiao Yao ◽

Houhong He ◽

Jin Xue ◽

Jianfang Wang ◽

Huihui Jin ◽

...

Keyword(s):

Natural Products ◽

Ethanol Extract ◽

Accurate Method ◽

Morus Alba ◽

Strongly Correlated ◽

Bioactive Constituents ◽

Antiplatelet Aggregation ◽

Pharmacologically Active ◽

First Time ◽

Tof Ms

In Traditional Chinese Medicine (TCM), Mori ramulus (Chin.Ph.)—the dried twigs of Morus alba L.—is extensively used as an antirheumatic agent and also finds additional use in asthma therapy. As a pathological high xanthine oxidase (XO, EC 1.1.3.22) activity is strongly correlated to hyperuricemy and gout, standard anti-hyperuremic therapy typically involves XO inhibitors like allopurinol, which often cause adverse effects by inhibiting other enzymes involved in purine metabolism. Mori ramulus may therefore be a promissing source for the development of new antirheumatic therapeutics with less side effects. Coumarins, one of the dominant groups of bioactive constituents of M. alba, have been demonstrated to possess anti-inflammatory, antiplatelet aggregation, antitumor, and acetylcholinesterase (AChE) inhibitory activities. The combination of HPLC (DAD) and Q-TOF technique could give excellent separating and good structural characterization abilities which make it suitable to analyze complex multi-herbal extracts in TCM. The aim of this study was to develop a HPLC (DAD)/ESI-Q-TOF-MS/MS method for the identification and profiling of pharmacologically active coumarin glycosides in Mori ramulus refined extracts for used in TCM. This HPLC (DAD)/ESI-Q-TOF-MS/MS method provided a rapid and accurate method for identification of coumarin glycosides—including new natural products described here for the first time—in the crude extract of M. alba L. In the course of this project, two novel natural products moriramulosid A (umbelliferone-6-β-d-apiofuranosyl-(1→6)-β-d-glucopyranoside) and moriramulosid B (6-[[6-O-(6-deoxy-α-l-mannopyranosyl)-β-d-glucopyranosyl]oxy]-2H-1-benzopyran-1-one) were newly discovered and the known natural product Scopolin was identified in M. alba L. for the first time.

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Thermal properties of large main-belt asteroids observed by Herschel PACS

Astronomy and Astrophysics ◽

10.1051/0004-6361/202037718 ◽

2020 ◽

Vol 638 ◽

pp. A84

Author(s):

V. Alí-Lagoa ◽

T. G. Müller ◽

C. Kiss ◽

R. Szakáts ◽

G. Marton ◽

...

Keyword(s):

Adaptive Optics ◽

Thermal Inertia ◽

Physical Models ◽

Absolute Calibration ◽

Calibration Error ◽

Main Belt ◽

Infrared Observations ◽

Fine Grained ◽

Shape Models ◽

First Time

Non-resolved thermal infrared observations enable studies of thermal and physical properties of asteroids via thermo-physical models provided the shape and rotational properties of the target are well determined. We used calibration-programme Herschel PACS data (70, 100, 160 μm) and state-of-the-art shape models derived from adaptive-optics observations and/or optical light curves to constrain for the first time the thermal inertia of twelve large main-belt asteroids. We also modelled previously well-characterised targets such as (1) Ceres or (4) Vesta as they constitute important benchmarks. Using the scale as a free parameter, most targets required a re-scaling ~5% consistent with what would be expected given the absolute calibration error bars. This constitutes a good cross-validation of the scaled shape models, although some targets required larger re-scaling to reproduce the IR data. We obtained low thermal inertias typical of large main belt asteroids studied before, which continues to give support to the notion that these surfaces are covered by fine-grained insulating regolith. Although the wavelengths at which PACS observed are longwards of the emission peak for main-belt asteroids, they proved to be extremely valuable to constrain size and thermal inertia and not too sensitive to surface roughness. Finally, we also propose a graphical approach to help examine how different values of the exponent used for scaling the thermal inertia as a function of heliocentric distance (i.e. temperature) affect our interpretation of the results.

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Carbon Stars and Interstellar Dust

International Astronomical Union Colloquium ◽

10.1017/s025292110006752x ◽

1977 ◽

Vol 45 ◽

pp. 181-185

Author(s):

Stanisław Krawczyk ◽

Janina Krempeć ◽

Janusz Gertner

Keyword(s):

Thermal Radiation ◽

Interstellar Dust ◽

Carbonaceous Material ◽

The Other ◽

Major Constituent ◽

Interstellar Matter ◽

Carbon Stars ◽

Intrinsic Polarization ◽

Infrared Excess ◽

Infrared Observations

Extensive recent infrared observations of carbon stars (Gillet et al. 1971, Hackwell 1972, Morrison and Simon 1973) have shown that spectra of some cool variable carbon stars reveal infrared excesses, which are believed to be due to thermal radiation of the dust envelopes surrounding these stars. Observations of the visual intrinsic polarization made by Dyck et al. (1971) have confirmed this discovery. The relation existing between stars loosing their mass and those revealing the infrared excess (Geisel 1970) gives evidence for the reality of mass loss from cool variable carbon stars. On the other hand, several investigations (Kamijo 1967, Donn et al. 1968, Salpeter 1974), although differing considerably in details, do agree that conditions in the atmospheres of cool carbon stars are appropriate for the condensation of carbon grains. Hence, it is believed that evolutionary advanced cool variable carbon stars supply carbonaceous material, mainly graphite, into the interstellar matter, in which carbon seems to be the major constituent (Donn et al. 1968).

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On producers of cosmic organic compounds: exploring the boron abundance in lithium-rich K giant stars

Proceedings of the International Astronomical Union ◽

10.1017/s1743921317006871 ◽

2017 ◽

Vol 13 (S332) ◽

pp. 237-241 ◽

Cited By ~ 1

Author(s):

N. A. Drake ◽

R. de la Reza ◽

V. V. Smith ◽

K. Cunha

Keyword(s):

Organic Compounds ◽

Organic Material ◽

Emission Lines ◽

Low Mass Stars ◽

Strong Emission ◽

Giant Stars ◽

First Approximation ◽

Low Mass ◽

Stellar Interiors ◽

First Time

AbstractThe element boron belongs, together with lithium and beryllium, to a known trio of important elements for the study of evolutionary processes in low mass stars. Because B is the least fragile of this trio to be destroyed in the stellar interiors, it can be used to test if the Li enrichment is of planetary origin. Here, for the first time, boron lines are examined in the UV for four giants with different degrees of large Li enrichment by means of observations with the Hubble telescope. Two main results are found in our study. One is that to first approximation B abundances appear not to be in excess, invalidating the planet engulfment mechanism. The second one is that the two stars with very large Li abundances present emission lines indicating that quite strong active chromospheres are acting in these very Li-rich giants. These new results obtained from the UV complement our recent studies in the mid-IR (de la Rezaet al.2015) where strong emission-line features of organic material were found in the spectra of some Li-rich stars.

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