Academic literature on the topic 'WG2300'

ABSTRACT Quadruply lensed quasars are extremely rare objects, but incredibly powerful cosmological tools. Only few dozen are known in the whole sky. Here we present the spectroscopic confirmation of two new quadruplets WG0214-2105 and WG2100-4452 discovered by Agnello & Spiniello (2018) within the Dark Energy Survey public footprints. We have conducted spectroscopic follow-up of these systems with the Southern African Large Telescope as part of a program that aims at confirming the largest possible number of strong gravitational lenses in the equatorial and Southern hemisphere. For both systems, we present the sources spectra that allowed us to estimate their redshifts and unambiguously confirm their lensing nature. For the brighter deflector (WG2100-4452) we measure the spectroscopic redshift and the stellar velocity dispersion from optical absorption lines in the spectrum. For the other system we infer the lens redshift from photometry, being the quality of the spectra not good enough. We obtain photometry for both lenses, directly from multiband images, isolating the lenses from the quasars. One of the quadruplets, WG0214-2105, was also observed by Pan-STARRS, allowing us to estimate the apparent brightness of each quasar image at two different epochs, and thus to find evidence for flux variability. This result could suggest a microlensing event for the faintest components, although intrinsic variability cannot be excluded with only two epochs. Finally, we present simple lens models for both quadruplets, obtaining Einstein radii, singular isothermal ellipsoid velocity dispersions, ellipticities, and position angles of the lenses, as well as time-delay predictions assuming a concordance cosmological model.

Postmenopausal depression is closely associated with depletion of estrogen which modulates transmission of 5-HT, a key neurotransmitter that regulates stress-managing circuits in the brain. In this study, antidepressive efficacy of white ginseng (Panax gingseng Meyer, WG) was evaluated in stressed ovariectomized rats. Female Sprague Dawley rats were ovariectomized and repeatedly restraint stressed for 2 weeks (2h/day). Thirty minutes before restraint stress, rats were administered saline (control), WG 200 mg/kg (p.o.), WG 400 mg/kg (p.o.), or fluoxetine (PC, 10 mg/kg, i.p.). Tail suspension test (TST) and forced swimming test (FST) were performed to assess antidepressant effect of WG. After behavioral tests, levels of serum corticosterone (CORT) and hippocampal 5-HT were measured. Significant decrease of immobility time in TST and FST was shown in rats administered with PC or WG 400 compared to the control. WG200-treated rats showed remarkable reduction in immobility time of TST. PC, WG 200, or WG 400-administred group exhibited significant reduction of CORT compared to the control. PC or WG-treated rats exhibited remarkable increase in hippocampal 5-HT concentration compared to the control. Hippocampal 5-HT levels in WG groups were higher than those in the PC group. The present study demonstrated that WG had antidepressant efficacy in an animal model of menopausal depression. Treatment with WG enhanced hippocampal 5-HT level while suppressing depressive symptom and serum CORT level. These results provide evidence that WG plays an important role in activating serotonergic neurons in stressful situation, suggesting that WG might be a reliable natural alternative of antidepressant drugs to treat menopausal depression.

While natural areas are conservation lands that have been set aside for the purpose of preserving (or restoring) native plant and animal communities, they do require active management. One of the greatest management issues in natural areas is invasive plants. This 35-page publication provides land managers in Florida with current methods used to manage non-native plants. Written by Stephen F. Enloe, Ken Langeland, Jason Ferrell, Brent Sellers, and Greg MacDonald, and published by the UF/IFAS Agronomy Department, revised July 2018. http://edis.ifas.ufl.edu/wg209

Native to eastern and southern Asia, skunkvine is an invasive plant species introduced to the USDA Field Station near Brooksville before 1897. It has been included on the Florida Exotic Pest Plant Council List of Invasive Species as a Category I, defined as “species that are invading and disrupting native plant communities in Florida.” It was added to the Florida Noxious Weed List in 1999, making it illegal to possess, move, or release in Florida. This 3-page fact sheet was written by K. A. Langeland, R. K. Stocker, and D. M. Brazis, and published by the UF Department of Agronomy, February 2013. http://edis.ifas.ufl.edu/wg208

Aims: An eco-friendly coating emulsion prepared with mixture of oils of sesame and grape seed and alkyd-based waterborne varnish. The prepared emulsion applied four different wood substrates (walnut, beech, cedar and fir) in order to be investigated for some selected surface properties. Study Design: Several test methods were used to evaluate surface physicochemical properties of the coatings. The results obtained may be suggested for the selection of the best varnish-emulsion formulation for the improvement wood substrates and could provide useful evaluation of the test methods employed. Methodology: The wood species of Beech (Fagus sylvatica), Walnut (Juglans regia), Cedar (Cedrus libani) and Fir (Abies nordmandiana) were selected for the investigation. Commercially available alkyd based waterborne varnish was supplied ready to use form. Both sesame oil (Sesamum indicum L.) and grape seed oil (Vitis vinifera L.) were obtained from a company that produces them by the cold press technique commercially. Both oils were used as supplied, without additional processing. These oils were added to varnish at 10% and 20% proportions (volume/volume). The 5 μl of distilled water (surface tension of 72.6 mN /m) was applied on wood surface by a sessile droplet method to measure surface contact angles. The surface hardness and scratch resistance of the cured varnish layers on wood substrates were measured with using pencil hardness test procedure according to ASTM-D-3363 standard. Cross cut test also conducted according to EN ISO 2409 standard. Experimental Findings: It was found that coated walnut samples show 9.8 to 13.5° higher contact angle values in all directions while other three wood samples only show marginally different values (0.1 to 4.3°). The highest contact value of 35.9° and 35.8° was found with samples of Wg20 and Wg10 which treated 20- and 10% grape seed oil proportions in varnish emulsion. The oils of sesame and grape seed typically contain various proportions of fatty acids fractions which are constituents of a carboxylic acid with a long, aliphatic tail. These groups could be created a strong bond in combination with alkyd resin on wood surface. However, the surface energy distribution show only marginally changes regardless of treatment levels and conditions. Therefore, there is not any clear advantage observed on surface wood surface energy levels with coating applications. For 10% grape seed oil/varnish emulsion conditions, the hardness of coated surfaces found to be 3H, 3H, 2H, 2H for walnut, beech, fir and cedar, respectively. At 20% grape seed oil/varnish coatings, all coating surfaces show H level range. For cross hatch experiments, marginally similar trend was observed with 10-and 20% grape seed oil/varnish and 10% sesame oil/varnish emulsion coated wood species. Moreover, it was ranked 2 for fir, ranked 3 for beech and ranked 4 for cedar wood at 20% sesame oil/varnish emulsion coatings. It is noticeable that a correlation was observed between cross cut and surface scratch resistance properties with coated surfaces.

Die chloroplastidäre Genexpression ist durch charakteristische posttranskriptionelle Ereignisse, wie RNA-Prozessierung, RNA-Stabilität, RNA-Edierung oder RNA-Spleißen gekennzeichnet. Diese Prozesse werden fast ausnahmslos durch kernkodierte Proteine realisiert. PPR-Proteine (Pentatricopeptid repeat) stellen unter diesen kernkodierten Faktoren die größte Proteinfamilie dar. Das plastidäre Protein P67 gehört zur kleinen Untergruppe der PPR-Proteine mit SMR-Domäne (small MutS-related), deren molekulare Funktion im organellären Nukleinsäuremetabolismus bislang unverstanden ist. P67 zeigt eine nahe Verwandtschaft zu GUN1, einem zentralen Bestandteil retrograder Signalwege. Der hier analysierte P67-Knockout in Mais verursacht hellgrüne Phänotypen, eine drastische Reduktion der plastidären ATPase und Keimlingsletalität, was die essentielle Beteiligung von P67 an den Prozessen der Chloroplastenbiogenese und der Expression der plastidär kodierten ATPase-Untereinheiten vermuten lässt. Mögliche Implikationen eines fehlenden Phänotyps von Mutanten des P67-Orthologs aus Arabidopsis thaliana werden diskutiert. Eine Ausnahmestellung unter den Proteinen des chloroplastidären RNA-Metabolismus nimmt der einzige plastidär kodierte RNA-Reifungsfaktor MatK ein. Die genomische Position des matK-Gens im Intron der trnK-UUU ist in allen grünen Landpflanzen konserviert. MatK ist mit bakteriellen Maturasen verwandt, die spezifisch den Spleißprozess ihres Heimatintrons unterstützen. Dagegen deuten genetische und phylogenetische Studien zusätzliche MatK-Funktionen in trans an. In der vorliegenden Arbeit wird die spezifische Interaktion von MatK mit sieben Gruppe-IIA-Intron enthaltenden Transkripten in vivo gezeigt. Darunter befinden sich vier tRNA-Vorläufer (trnK-UUU mit dem matK-Heimatintron sowie trnV-UAC, trnI-GAU, trnA-UGC) und drei proteinkodierende Vorläufertranskripte (rpl2, rps12, atpF). Die Feinkartierung der MatK-Bindung im trnK-Heimatintron zeigt eine Assoziation mit multiplen Regionen. Organelläre Gruppe-II-Introns gelten als Vorläufer der spleißosomalen Introns. Die Assoziation mit multiplen Gruppe-II-Introns macht MatK somit zu einem interessanten Modell für die Evolution der transaktiven Spleißaktivität im Kern. Analysen der Expression von MatK und seinen Zielen deuten auf ein komplexes Muster möglicher regulativer Interaktionen hin.
Chloroplast gene expression is characterized by posttranscriptional events including RNA cleavage, RNA stability, RNA editing, and RNA splicing. The underlying processing machinery is almost exclusively encoded in the nucleus. PPR proteins (pentatricopeptide repeat) form the biggest protein family among these factors and are major players of the aforementioned posttranscriptional processes. The plastidial protein P67 is a member of a small subgroup of PPR proteins with SMR domain (small MutS-related). Molecular functions of this protein family in organellar nucleic acid metabolism are yet unknown. P67 is a close relative of GUN1, an essential component of the chloroplast to nucleus retrograde signalling pathway. It is shown here that a P67 knockout in maize causes pale green phenotypes, a dramatic reduction in ATPase levels, and seedling lethality. This indicates an essential role of P67 for chloroplast biogenesis and expression of the plastid encoded ATPase. The finding that mutants of the P67-orthologe in Arabidopsis lack a phenotype is discussed against the background of physiological differences between maize and Arabidopsis. A special case among proteins involved in plastid RNA metabolism is MatK - the only plastid encoded RNA maturation factor. The genomic position of the matK gene in the trnK-UUU intron is conserved throughout autotrophic land plants. MatK is related to bacterial maturases - highly specific splice factors supporting splice processes of their respective home introns. There is, however, indirect genetic and phylogenetic evidence that MatK acts also in trans as a common plastidial splice factor serving various group II introns. This study shows that MatK interacts specifically with seven group IIA introns in vivo. Among them are four tRNA precursor transcripts (trnK-UUU including the matK home intron as well as trnV-UAC, trnI-GAU, trnA-UGC) and three protein-coding precursors (rpl2, rps12, atpF). Fine mapping of MatK binding sites within the trnK home intron uncovers protein RNA interactions with diverse intron regions. Organellar introns have been suggested as evolutionary ancestors of nuclear spliceosomal introns. Consequently, association of MatK with multiple group II intron ligands makes the plastidial maturase an attractive model for an early trans-acting nuclear splice activity. Analyses of the expression of MatK and its targets revealed a complex pattern of possible regulatory interactions.