1,820 research outputs found
Modeling Solar Lyman Alpha Irradiance
Solar Lyman alpha irradiance is estimated from various solar indices using linear regression analyses. Models developed with multiple linear regression analysis, including daily values and 81-day running means of solar indices, predict reasonably well both the short- and long-term variations observed in Lyman alpha. It is shown that the full disk equivalent width of the He line at 1083 nm offers the best proxy for Lyman alpha, and that the total irradiance corrected for sunspot effect also has a high correlation with Lyman alpha
The impact of multiple sclerosis on the identity of mothers in Italy
Purpose: This paper reports on one of the themes that emerged from the analysis of the study, regarding the perceived influence of multiple sclerosis (MS) on the identity of mothers in the socio-cultural context of Italy.
Method: In-depth interviews were conducted with 16 women at various stages of MS, with follow up interviews with seven of the women. Phenomenology guided the methodology and the analysis was conducted using interpretative phenomenological analysis.
Results: Through the research the value of motherhood to the women who participated emerged. The findings illustrated how many strove to maintain controlof their MS, which led to some making comparisons of themselves and other mothers and feeling different. Some women described how they adjusted their roles and found strength in being mothers but others spoke of their feelings of loss. Most women described living in the moment, appreciating the present and living each day as it came. Another significant experience was fear of stigma, both realized in the form of “pity” from others, and the perceived and actual associated stigma for their families. This contributed to why some women were reluctant to disclose their condition. The mothers who took part in this study differed in how they perceived their disabled identity.
Conclusion: Although this study was conducted in the socio-cultural setting of Italy, the findings have implications for professionals working with disabled mothers and women with MS in Italy and beyond; including recognizing the value associated with fully identifying oneself as a mother, rather than solely focusing on doingmothering tasks.
• Implications for Rehabilitation
• Professionals need to be mindful of the value of motherhood for women with multiple sclerosis.
• Professionals should support women who feel like they are battling with maintaining control of their multiple sclerosis, who may be adjusting their identity as mothers; recognizing that they may be influenced by the stage of their multiple sclerosis and whether they were diagnosed before or after having their children.
• Women can have feelings of loss related to their ability to fully participate in their children’s lives and professionals should work with women to help them identify the value of their mothering role not only in physically participating in activities but also in being emotionally and physically present as a mother
Power Spectrum Analysis of Physikalisch-Technische Bundesanstalt Decay-Rate Data: Evidence for Solar Rotational Modulation
Evidence for an anomalous annual periodicity in certain nuclear decay data
has led to speculation concerning a possible solar influence on nuclear
processes. We have recently analyzed data concerning the decay rates of Cl-36
and Si-32, acquired at the Brookhaven National Laboratory (BNL), to search for
evidence that might be indicative of a process involving solar rotation.
Smoothing of the power spectrum by weighted-running-mean analysis leads to a
significant peak at frequency 11.18/yr, which is lower than the equatorial
synodic rotation rates of the convection and radiative zones. This article
concerns measurements of the decay rates of Ra-226 acquired at the
Physikalisch-Technische Bundesanstalt (PTB) in Germany. We find that a similar
(but not identical) analysis yields a significant peak in the PTB dataset at
frequency 11.21/yr, and a peak in the BNL dataset at 11.25/yr. The change in
the BNL result is not significant since the uncertainties in the BNL and PTB
analyses are estimated to be 0.13/yr and 0.07/yr, respectively. Combining the
two running means by forming the joint power statistic leads to a highly
significant peak at frequency 11.23/yr. We comment briefly on the possible
implications of these results for solar physics and for particle physics.Comment: 15 pages, 13 figure
Solar Irradiance Variations on Active Region Time Scales
The variations of the total solar irradiance is an important tool for studying the Sun, thanks to the development of very precise sensors such as the ACRIM instrument on board the Solar Maximum Mission. The largest variations of the total irradiance occur on time scales of a few days are caused by solar active regions, especially sunspots. Efforts were made to describe the active region effects on total and spectral irradiance
Sequential sampling for predators in cotton
The Oklahoma Cooperative Extension Service periodically issues revisions to its publications. The most current edition is made available. For access to an earlier edition, if available for this title, please contact the Oklahoma State University Library Archives by email at [email protected] or by phone at 405-744-6311
1,2,6-thiadiazinones as novel narrow spectrum calcium/calmodulin-dependent protein kinase kinase 2 (CaMKK2) inhibitors
We demonstrate for the first time that 4H-1,2,6-thiadiazin-4-one (TDZ) can function as a chemotype for the design of ATP-competitive kinase inhibitors. Using insights from a co-crystal structure of a 3,5-bis(arylamino)-4H-1,2,6-thiadiazin-4-one bound to calcium/calmodulin-dependent protein kinase kinase 2 (CaMKK2), several analogues were identified with micromolar activity through targeted displacement of bound water molecules in the active site. Since the TDZ analogues showed reduced promiscuity compared to their 2,4-dianilinopyrimidine counter parts, they represent starting points for development of highly selective kinase inhibitors
Further Evidence Suggestive of a Solar Influence on Nuclear Decay Rates
Recent analyses of nuclear decay data show evidence of variations suggestive
of a solar influence. Analyses of datasets acquired at the Brookhaven National
Laboratory (BNL) and at the Physikalisch-Technische Bundesanstalt (PTB) both
show evidence of an annual periodicity and of periodicities with sidereal
frequencies in the neighborhood of 12.25 year^{-1} (at a significance level
that we have estimated to be 10^{-17}). It is notable that this implied
rotation rate is lower than that attributed to the solar radiative zone,
suggestive of a slowly rotating solar core. This leads us to hypothesize that
there may be an "inner tachocline" separating the core from the radiative zone,
analogous to the "outer tachocline" that separates the radiative zone from the
convection zone. The Rieger periodicity (which has a period of about 154 days,
corresponding to a frequency of 2.37 year^{-1}) may be attributed to an r-mode
oscillation with spherical-harmonic indices l=3, m=1, located in the outer
tachocline. This suggests that we may test the hypothesis of a solar influence
on nuclear decay rates by searching BNL and PTB data for evidence of a
"Rieger-like" r-mode oscillation, with l=3, m=1, in the inner tachocline. The
appropriate search band for such an oscillation is estimated to be 2.00-2.28
year^{-1}. We find, in both datasets, strong evidence of a periodicity at 2.11
year^{-1}. We estimate that the probability of obtaining these results by
chance is 10^{-12}.Comment: 12 pages, 6 figures, v2 has a color corrected Fig 6, a corrected
reference, and a corrected typ
A hydrodynamic study of the circumstellar envelope of alpha Scorpii
Context: Both the absolute mass-loss rates and the mechanisms that drive the
mass loss of late-type supergiants are still not well known. Binaries such as
alpha Sco provide the most detailed empirical information about the winds of
these stars.
Aims: The goal was to improve the binary technique for the determination of
the mass-loss rate of alpha Sco A by including a realistic density distribution
and velocity field from hydrodynamic and plasma simulations.
Methods: We performed 3D hydrodynamic simulations of the circumstellar
envelope of alpha Sco in combination with plasma simulations accounting for the
heating, ionization, and excitation of the wind by the radiation of alpha Sco
B. These simulations served as the basis for an examination of circumstellar
absorption lines in the spectrum of alpha Sco B as well as of emission lines
from the Antares nebula.
Results: The present model of the extended envelope of alpha Sco reproduces
some of the structures that were observed in the circumstellar absorption lines
in the spectrum of alpha Sco B. Our theoretical density and velocity
distributions of the outflow deviate considerably from a spherically expanding
model, which was used in previous studies. This results in a higher mass-loss
rate of (2 +/- 0.5) x 10^-6 M_sun/yr. The hot H II region around the secondary
star induces an additional acceleration of the wind at large distances from the
primary, which is seen in absorption lines of Ti II and Cr II at -30 km/s.Comment: 12 pages, 14 figures, accepted for publication in A&
Silicates in D-type symbiotic stars: an ISO overview
We investigate the IR spectral features of a sample of D-type symbiotic
stars. Analyzing unexploited ISO-SWS data, deriving the basic observational
parameters of dust bands and comparing them with respect to those observed in
other astronomical sources, we try to highlight the effect of environment on
grain chemistry and physic. We find strong amorphous silicate emission bands at
10 micron and 18 micron in a large fraction of the sample. The analysis of the
10 micron band, along with a direct comparison with several astronomical
sources, reveals that silicate dust in symbiotic stars shows features between
the characteristic circumstellar environments and the interstellar medium. This
indicates an increasing reprocessing of grains in relation to specific
symbiotic behavior of the objects. A correlation between the central wavelength
of the 10 and 18 micron dust bands is found. By the modeling of IR spectral
lines we investigate also dust grains conditions within the shocked nebulae.
Both the unusual depletion values and the high sputtering efficiency might be
explained by the formation of SiO moleculae, which are known to be a very
reliable shock tracer. We conclude that the signature of dust chemical
disturbance due to symbiotic activity should be looked for in the outer,
circumbinary, expanding shells where the environmental conditions for grain
processing might be achieved. Symbiotic stars are thus attractive targets for
new mid-infrared and mm observations.Comment: 24 pages, 6 figures, 5 tables - to be published in A
Rocket calibration of the Nimbus 6 solar constant measurements
Total solar irradiance was observed simultaneously outside the earth's atmosphere by three types of absolute cavity radiometers and duplicates of four of the Nimbus 6 Earth Radiation Budget (ERB) solar channels in a June 1976 sounding rocket experiment. The preliminary average solar constant result from the cavity radiometers is 1367 Wm (-2) with an uncertainty of less than + or - 0.5% in S.I. units. The duplicate ERB channel 3 on the rocket gave a value of 1389 Wm (-2) which agreed exactly with the Nimbus 6 ERB channel 3 measurement made simultaneously with the rocket flight
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