1,123 research outputs found
Wind Variability in BZ Camelopardalis
(Shortened) Sequences of spectra of the nova-like cataclysmic variable (CV)
BZ Cam were acquired on 9 nights in 2005-2006 in order to study the time
development of episodes of wind activity known to occur frequently in this
star. We confirm past results that the P-Cygni absorption components of the
lines mostly evolve from a higher expansion velocity to lower velocity as an
episode progresses. We also commonly find blueshifted emission components in
the Halpha line profile, whose velocities and durations strongly suggest that
they are also due to the wind. We suggest that the progression from larger to
smaller expansion velocities is due the higher velocity portions of a wind
concentration moving beyond the edge of the continuum light of the disk first,
leaving a net redward shift of the remaining absorption profile. We also derive
a new orbital ephemeris for BZ Cam, using the radial velocity of the core of
the HeI 5876AA line, finding P = 0.15353(4). Using this period the wind
episodes in BZ Cam are found to be concentrated near inferior conjuction of the
emission line source. This result confirms that the winds in nova-like CVs are
often phase dependent, in spite of the puzzling implication that such winds
lack axisymmetry. We argue that the radiation-driven wind in BZ Cam receives an
initial boost by acting on gas that has been lifted above the disk by the
interaction of the accretion stream with the disk, thereby imposing flickering
time scales onto the wind events, as well as leading to an orbital modulation
of the wind due to the non-axisymmetric nature of the stream/disk interaction.Comment: The Astronomical Journal, in pres
Evolution of the sugar receptors in insects
<p>Abstract</p> <p>Background</p> <p>Perception of sugars is an invaluable ability for insects which often derive quickly accessible energy from these molecules. A distinctive subfamily of eight proteins within the gustatory receptor (Gr) family has been identified as sugar receptors (SRs) in <it>Drosophila melanogaster </it>(Gr5a, Gr61a, and Gr64a-f). We examined the evolution of these SRs within the 12 available Drosophila genome sequences, as well as three mosquito, two moth, and beetle, bee, and wasp genome sequences.</p> <p>Results</p> <p>While most Drosophila species retain all eight genes, we find that the three Drosophila subgenus species have lost Gr64d, while <it>D. grimshawi </it>and the <it>D. pseudoobscura/persimilis </it>sibling species have also lost Gr5a function. The entire Gr64 gene complex was also duplicated in the <it>D. grimshawi </it>lineage, but only one potentially functional copy of each gene has been retained. The numbers of SRs range from two in the hymenopterans <it>Apis mellifera </it>and <it>Nasonia vitripennis </it>to 16 in the beetle <it>Tribolium castaneum</it>. An unusual aspect is the evolution of a novel exon from intronic sequence in an expanded set of four SRs in <it>Bombyx mori </it>(BmGr5-8), which appears to be the first example of such exonization in insects. Twelve intron gains and 63 losses are inferred within the SR family.</p> <p>Conclusion</p> <p>Examination of the SRs in these fly, mosquito, moth, beetle, and hymenopteran genome sequences reveals that they appear to have originated independently from single ancestral genes within the dipteran and coleopteran lineages, and two genes in the lepidopteran and hymenopteran lineages. The origin of the insect SRs will eventually be illuminated by additional basal insect and arthropod genome sequences.</p
Super normal design for extraordinary bodies:A design manifesto
This collection identifies the key tensions and conflicts being debated within the field of critical disability studies and provides both an outline of the field in its current form and offers manifestos for its future direction
Interventions That Reduce Anxiety and Depression to Support Mediation of Lifestyle Balance in Middle School Students
Mental health disorders are internationally known as a leading cause of disability throughout almost 20% of the adolescent population experiencing devastating mental health problems. Current statistics note that the prevalence of impaired mental health within this population has increased by 21% from 2001 to 2011, indicating a continuation of severe effects from poor mental health on this vulnerable population (Danielson et al., 2020). Allison et al. (2014) estimated that at the time the article was written, 14 million children in the United States had a mental health disorder that interfered with their daily life. Research from the Centers for Disease Control and Prevention (CDC, 2020) stated that 4.4 million children between the ages of three and 17 were diagnosed and impacted by anxiety, while 1.9 million children within the same age range were diagnosed with depression
Simulations of a New Continuous Steelmaking Process
A new continuous steelmaking process has been designed in an effort to reduce meltshop costs and increase productivity beyond the possibilities of current EAF-LMF-CC meltshops. This paper discusses possible operational performance based on industrially-verified kinetic, thermodynamic, and heat-transfer models. Dynamic simulations predict variations in steel chemistry and temperature, resulting from steel treatment and upsets. Savings in costs are projected because of increased metallic yield, lower energy requirements, more efficient use of deoxidants and alloys, fewer man-hours per ton, and decreased capital investment
The prevention of rhesus immunization
The results of a rhesus prevention programme are reported, confirming that rhesus immunization is a preventable condition. The procedure of foeto-maternal transfusion using the KJeihauer technique did not appear to allow the detection of high risk cases. It is argued that anti-D immunoglobulin may be administered without the prior determination of foetal blood group and the detection of foetal red cells in the maternal circulation and that all rhesus-negative women should be given passive immunization as a routine shortly after delivery
Real-World Dosing of OnabotulinumtoxinA and IncobotulinumtoxinA for Cervical Dystonia and Blepharospasm: Results from TRUDOSE and TRUDOSE II
The real-world use of onabotulinumtoxinA and incobotulinumtoxinA for cervical dystonia and blepharospasm treatment was assessed in two separate retrospective studies using identical protocols (TRUDOSE and TRUDOSE II). The studies were conducted in Mexico, Norway, and United Kingdom and designed to evaluate dose utilization of the two botulinum toxins in clinical practice. Eighty-three patients treated with both onabotulinumtoxinA and incobotulinumtoxinA for ≥2 years for each botulinum toxin were included, (52, cervical dystonia; 31, blepharospasm). All patients switched from onabotulinumtoxinA to incobotulinumtoxinA for administrative/financial reasons. A range of dose ratios (incobotulinumtoxinA to onabotulinumtoxinA) was reported; with the majority of dose ratios being >1. The mean dose ratio was >1 regardless of the study site or underlying clinical condition. The inter-injection interval was significantly longer for onabotulinumtoxinA versus incobotulinumtoxinA when assessed for all patients (15.5 vs. 14.3 weeks; p = 0.006), resulting in fewer onabotulinumtoxinA treatments over the study time period. Consistent with product labeling, no single fixed-dose ratio exists between incobotulinumtoxinA and onabotulinumtoxinA. The dosage of each should be individualized based on patient needs and used as per product labeling. These real-world utilization data may have pharmacoeconomic implications.publishedVersio
Inhibition of the Redox Function of APE1/Ref-1 in Myeloid Leukemia Cell Lines Results in a Hypersensitive Response to Retinoic Acid-induced Differentiation and Apoptosis
Objective
The standard of care for promyelocytic leukemia includes use of the differentiating agent all-trans retinoic acid (RA) and chemotherapy. RA induces cell differentiation through retinoic acid receptor (RAR) transcription factors. Because redox mechanisms influence how readily transcription factors bind to DNA response elements (RARE), the impact of small molecule (E3330) inhibition of the redox regulatory protein, apurinic-apyrimidinic endonuclease/redox effector factor (APE1/Ref-1) on RAR DNA binding and function in RA-induced myeloid leukemia cell differentiation and apoptosis was investigated.
Materials and Methods
The redox function of APE1 was studied using the small molecule inhibitor E3330 in HL-60 and PLB acute myeloid leukemia cells. Electrophoretic mobility shift assays were employed to determine effect of inhibitor on APE1/Ref-1 redox signaling function. Trypan blue assays, Annexin-V/propidium iodide and CD11b staining, and real-time polymerase chain reaction analyses were employed to determine survival, apoptosis, and differentiation status of cells in culture.
Results
RARα binds to its RARE in a redox-dependent manner mediated by APE1/Ref-1 redox regulation. Redox-dependent RAR-RARE binding is blocked by E3330, a small molecule redox inhibitor of APE1/Ref-1. Combination treatment of RA + E3330 results in a profound hypersensitivity of myeloid leukemia cells to RA-induced differentiation and apoptosis. Additionally, redox inhibition by E3330 results in enhanced RAR target gene, BLR-1, expression in myeloid leukemia cells.
Conclusions
The redox function of APE1/Ref-1 regulates RAR binding to its DNA RAREs influencing the response of myeloid leukemia cells to RA-induced differentiation. Targeting of APE1/Ref-1 redox function may allow manipulation of the retinoid response with therapeutic implications
Evolution of the Gene Lineage Encoding the Carbon Dioxide Receptor in Insects
A heterodimer of the insect chemoreceptors Gr21a and Gr63a has been shown to be the carbon dioxide receptor in Drosophila melanogaster (Meigen) (Diptera: Drosophilidae). Comparison of the genes encoding these two proteins across the 12 available drosophilid fly genomes allows refined definition of their N-termini. These genes are highly conserved, along with a paralog of Gr21a, in the Anopheles gambiae, Aedes aegypti, and Culex pipiens mosquitoes, as well as in the silk moth Bombyx mori and the red flour beetle Tribolium castaneum. In the latter four species we name these three proteins Gr1, Gr2, and Gr3. Intron evolution within this distinctive three gene lineage is considerable, with at least 13 inferred gains and 39 losses. Surprisingly, this entire ancient gene lineage is absent from all other available more basal insect and related arthropod genomes, specifically the honey bee, parasitoid wasp, human louse, pea aphid, waterflea, and blacklegged tick genomes. At least two of these species can detect carbon dioxide, suggesting that they evolved other means to do so
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