Polar Profile Research Articles

Accelerated Development of COVID-19 Vaccines: Technology Platforms, Benefits, and Associated Risks.

Multiple preventive COVID-19 vaccines have been developed during the ongoing SARS coronavirus (CoV) 2 pandemic, utilizing a variety of technology platforms, which have different properties, advantages, and disadvantages. The acceleration in vaccine development required to combat the current pandemic is not at the expense of the necessary regulatory requirements, including robust and comprehensive data collection along with clinical product safety and efficacy evaluation. Due to the previous development of vaccine candidates against the related highly pathogenic coronaviruses SARS-CoV and MERS-CoV, the antigen that elicits immune protection is known: the surface spike protein of SARS-CoV-2 or specific domains encoded in that protein, e.g., the receptor binding domain. From a scientific point of view and in accordance with legal frameworks and regulatory practices, for the approval of a clinic trial, the Paul-Ehrlich-Institut requires preclinical testing of vaccine candidates, including general pharmacology and toxicology as well as immunogenicity. For COVID-19 vaccine candidates, based on existing platform technologies with a sufficiently broad data base, pharmacological–toxicological testing in the case of repeated administration, quantifying systemic distribution, and proof of vaccination protection in animal models can be carried out in parallel to phase 1 or 1/2 clinical trials. To reduce the theoretical risk of an increased respiratory illness through infection-enhancing antibodies or as a result of Th2 polarization and altered cytokine profiles of the immune response following vaccination, which are of specific concern for COVID-19 vaccines, appropriate investigative testing is imperative. In general, phase 1 (vaccine safety) and 2 (dose finding, vaccination schedule) clinical trials can be combined, and combined phase 2/3 trials are recommended to determine safety and efficacy. By applying these fundamental requirements not only for the approval and analysis of clinical trials but also for the regulatory evaluation during the assessment of marketing authorization applications, several efficacious and safe COVID-19 vaccines have been licensed in the EU by unprecedentedly fast and flexible procedures. Procedural and regulatory–scientific aspects of the COVID-19 licensing processes are described in this review.

Magnetic flux structuring of the quiet Sun internetwork

Context. The small-scale magnetism of the quiet Sun has been investigated by various means in recent decades. It is now well established that the quiet Sun contains in total more magnetic flux than active regions and represents an important reservoir of magnetic energy. But the nature and evolution of these fields remain largely unknown. Aims. We investigate the solar-cycle and center-to-limb variations of magnetic-flux structures at small scales in internetwork regions of the quiet Sun. Methods. We used Hinode SOT/SP data from the irradiance program between 2008 and 2016. Maps of the magnetic-flux density are derived from the center-of gravity method applied to the circular polarization profiles in the FeI 630.15 nm and FeI 630.25 nm lines. To correct the maps from the instrumental smearing of the telescope, we applied a deconvolution method based on a principal component analysis of the line profiles and on a Richardson-Lucy deconvolution of their coefficients. We took defocus effects and the diffraction of the SOT telescope into account. We then performed a spectral analysis of the spatial fluctuations of the magnetic-flux density in 10″ × 10″ internetwork regions spanning a wide range of latitudes from ±70° to the equator. Results. At low and mid latitudes the power spectra normalized by the mean value of the unsigned flux in the regions do not vary significantly with the solar cycle. However at solar maximum for one scan in the activity belt showing an enhanced network, a marginal increase in the power of the magnetic fluctuations is observed at granular and larger scales in the internetwork. At high latitudes, we observe variations at granular and larger scales where the power decreases at solar maximum. At all the latitudes the power of the magnetic fluctuations at scales smaller than 0.5″ remains constant throughout the solar cycle. Conclusions. At the equator the unsigned flux density is related to the vertical component of the magnetic field, whereas at high latitudes this flux density is mainly related to the horizontal component and probe higher altitudes. Our results favor a small-scale dynamo that operates in the internetwork, but they show that the global dynamo also contributes to the internetwork fields. At solar maximum the high-latitude horizontal internetwork fields seem to be depleted from the structures at granular and larger scales that are seen at solar minimum, whereas the internetwork within enhanced network regions show more structures at those scales than at solar minimum.

Follicular Lymphoma Regulatory T Cell Function and Origin

Follicular Lymphoma (FL) is the most frequent indolent lymphoma and results from the malignant transformation of germinal center (GC) B cells. Among FL recurrent genetic alterations, some are not only oncogenic per se but favor the interactions of FL B cells with their microenvironment including in particular surrounding follicular helper T cells (Tfh). During normal GC reaction Tfh support early GC B-cell selection and differentiation whereas follicular regulatory T cells (Tfr) expand later and inhibit both Tfh activity and B-cell antibody secretion. Whereas the role of Tfh in human diseases is an intense matter of interest, very few data are available concerning the origin and function of human Tfr. We previously demonstrated that Tfh and Tfr proportions are increased within FL lymph nodes and FL-Tfh contribute, through a specific polarization profile, to FL B cell survival and drug resistance. Interestingly FL-Tfr expansion is correlated to the one of FL-Tfh but not FL-Treg. The aim of this work was to characterize human Tfr in non-malignant (chronically inflamed tonsils) and malignant (FL) settings through transcriptomic, DNA methylation, TCR repertoire, and functional studies. We demonstrated for the first time that human Tfr purified from FL samples and tonsils directly inhibit autologous Tfh proliferation and trigger a downregulation of the co-stimulatory markers CD86 and HLA-DR on autologous normal and malignant GC B cells. In agreement FL-Tfh proliferated less than tonsil-Tfh in situ and after in vitro restimulation. Moreover, we found that Tfr clustered with Treg at both transcriptomic and methylome levels including for the high demethylation level of the FOXP3 TSDR, suggesting a stable regulatory phenotype. However, TCR sequencing demonstrated that tonsil-Tfr shared a common repertoire only with tonsil-Tfh unlike tonsil-Treg, arguing for their peripheral unlike thymic origin. Conversely in FL, even if the majority of common clones were found between Tfr and Tfh, a small proportion of TCR repertoire was shared between Tfr and Treg. Altogether, these results are the first detailed characterization of human Tfr and challenge our current understanding of Tfr commitment pathway. FL-Tfr retain their capacity to inhibit Tfh thus questioning their role in FL and their potential as therapeutic target in this fatal malignancy. DisclosuresTarte:Roche: Consultancy; Novimmune: Research Funding; Celgene: Consultancy, Research Funding. Lamy:Roche: Consultancy, Honoraria.

IL-32γ Induces M2 Macrophage Polarization with Enhanced Ability of Macrophage-Mediated Drug Resistance in Myeloma Cells through STAT3 and NF-κB Activation

Background: Macrophages(MΦs) are an abundant and important component of multiple myeloma (MM) microenvironment, and support the survival of MM cells and promote their resistance to chemotherapy. It has been proposed that MΦs have great plasticity and can differentiate into 2 major polarized states, M1 (“classically activated”) and M2 (“alternatively activated”). M1 macrophages are considered to be anti-tumoural and pro-inflammatory, whereas M2 macrophages are characterized by efficient activity of tumour promotion and suppression of adaptive immunity.IL-32, a novel proinflammatory cytokine, has been found to play a crucial role in a variety of inflammatory diseases and cancers. In this study, we investigated the immunomodulatory effects and underlying mechanisms of IL-32γ on macrophage polarization and MΦ-mediated drug resistance in myeloma cells.Results: First, we found that both bone marrow supernatant and peripheral blood supernatant of MM patients showed significantly higher levels of IL-32 as compared with those of healthy controls. We also detected IL-32 in MM cell lines and M-CSF-induced MØs by qRT-PCR and Western blot, which showed that IL-32 expression was higher in MM cell lines than in MØs. We next investigated the polarization profiles and functional activities of IL-32γ-treated MØs. After stimulated with recombinant IL-32γ,MØs exhibited upregulated expression of cell-surface molecules and cytokines associated with M2 polarization(CD206,Dectin-1, and IL-10), while M1-polarizing marker(CD86) were down-regulated.Further, Western blot was applied to detect the inflammation molecular pathway in MØs, which showed that IL-32γ treatment activated the JAK-STAT3 pathway and NF-κB pathway. This pro-M2MØ polarization effect of IL-32γ was inhibited by the addition of specific inhibitors of STAT3 and NF-kB. Moreover, co-culture experiments revealed that IL-32γ-educated MØs provided a survival benefit to myeloma cells, as tested with several anti-myeloma agents including bortezomib and doxorubicin. The pro-survival effect was associated with less cleavage of caspase-3 and PARP in myeloma cells, and thus less apoptosis. The STAT3 and NF-κB inhibitors partially inhibited the observed IL-32γ-induced and MØs -mediated resistance to bortezomib in MM cells.Conclusions:IL-32γ could effectively induce the polarization of M2 MØs, leading to enhanced MØ-mediated drug resistance in myeloma cells as the result of activating the JAK-STAT3 and NF-κB pathways in MØs. DisclosuresNo relevant conflicts of interest to declare.

BZD9L1 sirtuin inhibitor: Identification of key molecular targets and their biological functions in HCT 116 colorectal cancer cells

BZD9L1 was previously described as a SIRT1/2 inhibitor with anti-cancer activities in colorectal cancer (CRC), either as a standalone chemotherapy or in combination with 5-fluorouracil. BZD9L1 was reported to induce apoptosis in CRC cells; however, the network of intracellular pathways and crosstalk between molecular players mediated by BZD9L1 is not fully understood. This study aimed to uncover the mechanisms involved in BZD9L1-mediated cytotoxicity based on previous and new findings for the prediction and identification of related pathways and key molecular players. BZD9L1-regulated candidate targets (RCTs) were identified using a range of molecular, cell-based and biochemical techniques on the HCT 116 cell line. BZD9L1 regulated major cancer pathways including Notch, p53, cell cycle, NFκB, Myc/MAX, and MAPK/ERK signalling pathways. BZD9L1 also induced reactive oxygen species (ROS), regulated apoptosis-related proteins, and altered cell polarity and adhesion profiles. In silico analyses revealed that most RCTs were interconnected, and were involved in the modulation of catalytic activity, metabolism and transcription regulation, response to cytokines, and apoptosis signalling pathways. These RCTs were implicated in p53-dependent apoptosis pathway. This study provides the first assessment of possible associations of molecular players underlying the cytotoxic activity of BZD9L1, and establishes the links between RCTs and apoptosis through the p53 pathway.

Pontibaca salina sp. nov., isolated from marine sediment.

A Gram-stain-negative, oval or short rod-shaped, non-motile, aerobic bacterium, designated strain S1109LT, was isolated from a marine sediment in Weihai, PR China. Cells were oxidase positive and catalase positive. Growth of strain S1109LT occurred at 10-40°C (optimum, 30-33°C), pH 6.5-10.0 (optimum, 7.0-8.0) and in the presence of 1-21% (optimum, 4-6%) (w/v) NaCl. 16S rRNA gene sequence phylogeny indicated that strain S1109LT was associated with the genus Pontibaca of the family Rhodobacteraceae because it showed the highest sequence similarity to Pontibaca methylaminivorans KCTC 22497T (97.5%). The average nucleotide identity (ANI) and the digital DNA-DNA hybridization (dDDH) scores between strain S1109LT and Pontibaca methylaminivorans KCTC 22497T were 74.6% and 18.7%. The major cellular fatty acids of strain S1109LT were C19:0 cyclo ω8c and C18:1 ω7c. The polar lipids profiles of strain S1109LT were phosphatidylglycerol, phosphatidylcholine, phosphatidylethanolamine and two unidentified lipids. Strain S1109LT contained ubiquinone-10 as the major respiratory quinone. The genomic DNA G + C content was 55.9mol%. On the basis of the evidence presented in this study, strain S1109LT is considered to represent a novel species of the genus Pontibaca, for which the name Pontibaca salina sp. nov. is proposed. The type strain of is S1109LT (= KCTC 82411T = MCCC 1H00441T).

Intraspecific variation in polar and nonpolar metabolite profiles of a threatened Caribbean coral.

Research aimed at understanding intraspecific variation among corals could substantially increase understanding of coral biology and improve outcomes of active restoration efforts. Metabolomics is useful for identifying physiological drivers leading to variation among genotypes and has the capacity to improve our selection of candidate corals that express phenotypes beneficial to restoration. Our study aims to compare metabolomic profiles among known, unique genotypes of the threatened coral Acropora cervicornis. In doing so, we seek information related to the physiological characteristics driving variation among genotypes, which could aid in identifying genets with desirable traits for restoration. We applied proton nuclear magnetic resonance (1H-NMR) and liquid chromatography-mass spectrometry (LC-MS) to identify and compare metabolomic profiles for seven unique genotypes of A. cervicornis that previously exhibited phenotypic variation in a common garden coral nursery. Significant variation in polar and nonpolar metabolite profiles was found among A. cervicornis genotypes. Despite difficulties identifying all significant metabolites driving separation among genotypes, our data support previous findings and further suggest metabolomic profiles differ among various genotypes of the threatened species A. cervicornis. The implementation of metabolomic analyses allowed identification of several key metabolites driving separation among genotypes and expanded our understanding of the A. cervicornis metabolome. Although our research is specific to A. cervicornis, these findings have broad relevance for coral biology and active restoration. Furthermore, this study provides specific information on the understudied A. cervicornis metabolome and further confirmation that differences in metabolome structure could drive phenotypic variation among genotypes.

Sub-micrometer pyroelectric tomography of AlScN films

We report on one- to three-dimensional characterization of the pyroelectric properties of aluminum scandium nitride. By means of the laser intensity modulation method, we reconstructed the in-depth distribution of the spontaneous polarization with sub-micrometer resolution. The reconstructed profiles of the spontaneous polarization indicate that the thermal diffusivity and its temperature-dependence differ significantly from what is reported for pure aluminum nitride, which we attribute to the dominant role of phonon-alloy scattering for the heat transfer.

Geometry and water accessibility of the inhibitor binding site of Na+-pump: Pulse- and CW-EPR study

Spin labels based on cinobufagin, a specific inhibitor of the Na,K-ATPase, have proved valuable tools to characterize the binding site of cardiotonic steroids (CTSs), which also constitutes the extracellular cation pathway. Because existing literature suggests variations in the physiological responses caused by binding of different CTSs, we extended the original set of spin-labeled inhibitors to the more potent bufalin derivatives. Positioning of the spin labels within the Na,K-ATPase site was defined and visualized by molecular docking. Although the original cinobufagin labels exhibited lower affinity, continuous-wave electron paramagnetic resonance spectra of spin-labeled bufalins and cinobufagins revealed a high degree of pairwise similarity, implying that these two types of CTS bind in the same way. Further analysis of the spectral lineshapes of bound spin labels was performed with emphasis on their structure (PROXYL vs. TEMPO), as well as length and rigidity of the linkers. For comparable structures, the dynamic flexibility increased in parallel with linker length, with the longest linker placing the spin label at the entrance to the binding site. Temperature-related changes in spectral lineshapes indicate that six-membered nitroxide rings undergo boat-chair transitions, showing that the binding-site cross section can accommodate the accompanying changes in methyl-group orientation. D2O-electron spin echo envelope modulation in pulse-electron paramagnetic resonance measurements revealed high water accessibilities and similar polarity profiles for all bound spin labels, implying that the vestibule leading to steroid-binding site and cation-binding sites is relatively wide and water-filled.

Changes in Bovine Colostrum Metabolites during Early Postpartum Period Revealed by 1H-NMR Metabolomics Approach

The objectives of this study were to characterize and compare non-volatile polar metabolite profiles of bovine colostrum, collected within 1 h and at 72 h after parturition, from crossbred Holstein cows raised in northeastern Thailand. The colostrum serum was characterized and compared using a non-targeted proton nuclear magnetic resonance (1H-NMR) technique combined with chemometric analysis. Results demonstrated that the main effect of post-parturition time provided a significant impact on the physical properties and major chemical constituents of colostrum, while the influence of farm origin and sampling month were likely undetectable. The 1H-NMR technique enabled to identify 45 non-volatile polar metabolites in the samples. Partial least-squares-discriminant analysis (PLS-DA) allowed discrimination of colostrum metabolome not only according to different times after parturition, but also the origins of the farm as well as sampling months. Differential metabolites were statistically identified as potential biomarkers accountable for the discrimination. Besides basic nutritive compounds (amino acids and sugars), several bioactive metabolites such as ascorbate, creatine, carnitine, choline, acetylcarnitine, N-acetylglucosamine, ornithine, orotate, and UPD-glucose could be successfully elucidated. Our finding reveals the application of non-targeted 1H-NMR metabolomics as an effective tool to assess the biomolecular profiles of bovine colostrum and their essential dynamics during the first three days after parturition.

An 86 GHz Search for Pulsars in the Galactic Center with the Atacama Large Millimeter / submillimeter Array

Abstract We report on the first pulsar and transient survey of the Galactic Center (GC) with the Atacama Large Millimeter/submillimeter Array (ALMA). The observations were conducted during the Global Millimeter VLBI Array campaign in 2017 and 2018. We carry out searches using time series of both total intensity and other polarization components in the form of Stokes parameters. We incorporate acceleration and its derivative in the pulsar search, and also search in segments of the entire observation to compensate for potential orbital motion of the pulsar. While no new pulsar is found, our observations yield the polarization profile of the GC magnetar PSR J1745−2900 at millimeter wavelength for the first time, which turns out to be nearly 100% linearly polarized. Additionally, we estimate the survey sensitivity placed by both system and red noise, and evaluate its capability of finding pulsars in orbital motion with either Sgr A* or a binary companion. We show that the survey is sensitive to only the most luminous pulsars in the known population and future observations with ALMA in Band-1 will deliver significantly deeper survey sensitivity on the GC pulsar population.

Magnetic field of the eclipsing binary UV Piscium

Aims. The goal of this work is to study magnetic fields of the cool, eclipsing binary star UV Piscium (UV Psc). This system contains two active late-type stars, UV Psc A (G5V) and B (K3V). To obtain a complete picture, the properties of both global and local magnetic field structures are studied for both components. Methods. High-resolution intensity and circular polarisation spectra, collected in 2016 with the ESPaDOnS spectropolarimeter at the CFHT, were used to analyse the magnetic field of UV Psc. To increase the signal-to-noise ratio, the multi-line technique of least-squares deconvolution (LSD) was used to obtain average Stokes IV profiles. Then, a Zeeman-Doppler imaging (ZDI) code was employed to obtain the large-scale magnetic field topology and brightness distribution for both components of UV Psc. In addition, the small-scale magnetic fields, not visible to ZDI, were studied using the Zeeman intensification of Fe I lines. Results. The orbital and fundamental parameters of the system were revised based on the new radial velocity measurements. Maps of the surface magnetic field for both components of UV Psc were obtained, the large-scale magnetic fields feature strong toroidal and non-axisymetric components. UV Psc A and B have average global field strengths of 137 G and 88 G, respectively. The small-scale fields are notably stronger, with average strengths of 2.5 and 2.2 kG, respectively. Only ∼5% of the total magnetic field strength is recovered with ZDI. Our results are in agreement with previous studies of partly-convective stars. Overall, UV Psc A has a stronger magnetic field compared to UV Psc B. Due to the eclipsing binary geometry, certain magnetic field features are not detectable using circular polarisation only. An investigation into theoretical linear polarisation profiles shows that they could be used to reveal antisymmetric components of the magnetic field. This result also has implications for the study of exoplanetary transit hosts. The successful use of Zeeman intensification shows the method’s ability to extract information on magnetic fields for stars rotating significantly more rapidly than in previous studies.

Polarization-density patterns of active particles in motility gradients

The colocalization of density modulations and particle polarization is a characteristic emergent feature of motile active matter in activity gradients. We employ the active-Brownian-particle model to derive precise analytical expressions for the density and polarization profiles of a single Janus-type swimmer in the vicinity of an abrupt activity step. Our analysis allows for an optional (but not necessary) orientation-dependent propulsion speed, as often employed in force-free particle steering. The results agree well with measurement data for a thermophoretic microswimmer presented in the companion paper [Söker etal., Phys. Rev. Lett. 126, 228001 (2021)10.1103/PhysRevLett.126.228001], and they can serve as a template for more complex applications, e.g., to motility-induced phase separation or studies of physical boundaries. The essential physics behind our formal results is robustly captured and elucidated by a schematic two-species "run-and-tumble" model.

The FAST Galactic Plane Pulsar Snapshot survey: I. Project design and pulsar discoveries ⋆ ⋆News and views on this paper

Discovery of pulsars is one of the main goals for large radio telescopes. The Five-hundred-meter Aperture Spherical radio Telescope (FAST), that incorporates an L-band 19-beam receiver with a system temperature of about 20 K, is the most sensitive radio telescope utilized for discovering pulsars. We designed the snapshot observation mode for a FAST key science project, the Galactic Plane Pulsar Snapshot (GPPS) survey, in which every four nearby pointings can observe a cover of a sky patch of 0.1575 square degrees through beam-switching of the L-band 19-beam receiver. The integration time for each pointing is 300 seconds so that the GPPS observations for a cover can be made in 21 minutes. The goal of the GPPS survey is to discover pulsars within the Galactic latitude of ± 10° from the Galactic plane, and the highest priority is given to the inner Galaxy within ± 5°. Up to now, the GPPS survey has discovered 201 pulsars, including currently the faintest pulsars which cannot be detected by other telescopes, pulsars with extremely high dispersion measures (DMs) which challenge the currently widely used models for the Galactic electron density distribution, pulsars coincident with supernova remnants, 40 millisecond pulsars, 16 binary pulsars, some nulling and mode-changing pulsars and rotating radio transients (RRATs). The follow-up observations for confirmation of new pulsars have polarization-signals recorded for polarization profiles of the pulsars. Re-detection of previously known pulsars in the survey data also leads to significant improvements in parameters for 64 pulsars. The GPPS survey discoveries are published and will be updated at http://zmtt.bao.ac.cn/GPPS/.

Activation and radwaste analysis for ITER soft X-ray camera

The Soft X-Ray camera (SXR) is designed to measure the polar profile of plasma X-ray emissivity with high spatial and temporal resolution. The camera is located on the Equatorial 12 Port Plug of ITER Tokamak. During the nuclear operation phase, a large number of high-energy neutrons are generated. These neutrons will activate the camera components and make them radioactive. In order to evaluate the activation of SXR's structural and shielding materials, an activation and radwaste analysis has been performed, and the results are summarized in this paper. A simplified model of all necessary parts of SXR is integrated into the ITER C-lite model for neutron transport. The activation of the components is calculated using the FISPACT-2007 code. The safety scenario SA2 for ITER activation calculations is recommended as irradiation history. The contact dose rate provides recommendations for the maintenance of SXR. The security risk of decay heat to SXR is analyzed. Specific activity and clearance index provide the basis for the classification of radwaste. The linear relationship between the neutron flux and activation parameters is obtained by expanding the neutron flux, so that the activation of SXR can be rapidly predicted according to the flux measured in the actual operation of ITER.

The thousand-pulsar-array programme on MeerKAT IV: Polarization properties of young, energetic pulsars

ABSTRACT We present observations of 35 high spin-down energy radio pulsars using the MeerKAT telescope. Polarization profiles and associated parameters are also presented. We derive the geometry for a selection of pulsars which show interpulse emission. We point out that, in several cases, these radio pulsars should also be seen in γ-rays but that improved radio timing is required to aid the high-energy detection. We discuss the relationship between the width of the radio profile and its high-energy detectability. Finally, we reflect on the correlation between the spin-down energy and the radio polarization fraction and the implications this may have for γ-ray emission.

Phase Manipulation‐Based Polarization Profile Realization and Hybrid Holograms Using Geometric Metasurface

The outstanding ability of optical metasurfaces to tailor light's amplitude, phase, and polarization with a subwavelength resolution has attracted big interest. A multifunctional metasurface device is reported and experimentally demonstrated that integrates an arbitrary polarization profile for image concealment and a computer‐generated hybrid hologram. Herein, a high‐resolution image is hidden in the polarization profile of the light beam, while the holographic images are encoded in its phase profile for the reconstruction of two different types of holographic images. The designed polarization profile is realized based on the superposition of two different phase profiles for circular polarization states with opposite handedness. This method can further extend the design degree of freedom in optical metasurfaces, which may open an alternative avenue for anticounterfeiting, optical image encoding, and optical information security.

The inflammatory pathogenesis of colorectal cancer.

The mutational landscape of colorectal cancer (CRC) does not enable predictions to be made about the survival of patients or their response to therapy. Instead, studying the polarization and activation profiles of immune cells and stromal cells in the tumour microenvironment has been shown to be more informative, thus making CRC a prototypical example of the importance of an inflammatory microenvironment for tumorigenesis. Here, we review our current understanding of how colon cancer cells interact with their microenvironment, comprised of immune cells, stromal cells and the intestinal microbiome, to suppress or escape immune responses and how inflammatory processes shape the immune pathogenesis of CRC.

Advancing Maritime Transparent Cirrus Detection Using the Advanced Baseline Imager “Cirrus” Band

AbstractWe describe a quantitative evaluation of maritime transparent cirrus cloud detection, which is based on Geostationary Operational Environmental Satellite – 16 (GOES-16) and developed with collocated Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) profiling. The detection algorithm is developed using one month of collocated GOES-16 Advanced Baseline Imager (ABI) Channel 4 (1.378 μm) radiance and CALIOP 0.532 μm column-integrated cloud optical depth (COD). First, the relationships between the clear-sky 1.378 μm radiance, viewing/solar geometry, and precipitable water vapor (PWV) are characterized. Using machine learning techniques, it is shown that the total atmospheric pathlength, proxied by airmass factor (AMF), is a suitable replacement for viewing zenith and solar zenith angles alone, and that PWV is not a significant problem over ocean. Detection thresholds are computed using the Ch. 4 radiance as a function of AMF. The algorithm detects nearly 50% of sub-visual cirrus (COD < 0.03), 80% of transparent cirrus (0.03 < COD < 0.3), and 90% of opaque cirrus (COD > 0.3). Using a conservative radiance threshold results in 84% of cloudy pixels being correctly identified and 4% of clear-sky pixels being misidentified as cirrus. A semi-quantitative COD retrieval is developed for GOES ABI based on the observed relationship between CALIOP COD and 1.378 μm radiance. This study lays the groundwork for a more complex, operational GOES transparent cirrus detection algorithm. Future expansion includes an over-land algorithm, a more robust COD retrieval that is suitable for assimilation purposes, and downstream GOES products such as cirrus cloud microphysical property retrieval based on ABI infrared channels.

Farmed mussels (Mytilus galloprovincialis) from the Black Sea reveal seasonal differences in their neutral and polar lipid fatty acids profile

Studies on the monthly variations of the fatty acid composition of the total lipids, the two neutral lipid fractions (NL) and the polar lipids (PoL) and the lipid quality parameters of Mediterranean mussel Mytilus galloprovincialis, harvested along the Bulgarian Black Sea coast, were conducted. The total lipid content ranged from 1.00 to 2.34 g.100 g−1 ww reaching maximum levels in March. The total sterol content increased significantly from spring to autumn. The polyunsaturated fatty acids (36%–79% of the total fatty acids) dominated over the saturated fatty acids (22%–55%) and monounsaturated fatty acids (7%–21%) throughout the studied period. Significant differences in the fatty acid distribution were observed between the lipid fractions. The polyunsaturated fatty acids (PUFA) constituted the major group in PoL within the period, while SFAs were the most abundant group in the NL fraction in February and April–August.​ In the PoL fraction, the omega-3 polyunsaturated fatty acids (n-3 PUFA) prevailed over the n-6 ones. The predominant PUFAs in both lipid fractions were eicosapentaenoic (EPA) and docosahexaenoic acids (DHA) (10%–58% of FA in NL and 22%–51% in PoL). M. galloprovincialis from the Black Sea presented favourable low values of n-6/n-3 ratios and nutritional indices of their lipids.