48 research outputs found
Exotic clouds in the local interstellar medium
The neutral interstellar medium (ISM) inside the Local Bubble (LB) has been
known to have properties typical of the warm neutral medium (WNM). However,
several recent neutral hydrogen (HI) absorption experiments show evidence for
the existence of at least several cold diffuse clouds inside or at the boundary
of the LB, with properties highly unusual relative to the traditional cold
neutral medium. These cold clouds have a low HI column density, and AU-scale
sizes. As the kinematics of cold and warm gas inside the LB are similar, this
suggests a possibility of all these different flavors of the local ISM
belonging to the same interstellar flow. The co-existence of warm and cold
phases inside the LB is exciting as it can be used to probe the thermal
pressure inside the LB. In addition to cold clouds, several discrete screens of
ionized scattering material are clearly located inside the LB.
The cold exotic clouds inside the LB are most likely long-lived, and we
expect many more clouds with similar properties to be discovered in the future
with more sensitive radio observations. While physical mechanisms responsible
for the production of such clouds are still poorly understood, dynamical
triggering of phase conversion and/or interstellar turbulence are likely to
play an important role.Comment: 10 pages, refereed, accepted for publication in the proceedings of
the "From the Outer Heliosphere to the Local Bubble: Comparisons of New
Observations with Theory" conference, Space Science Review
Track D Social Science, Human Rights and Political Science
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138414/1/jia218442.pd
Contribution of unmeasured anions to acid-base disorders and its association with altered demeanor in 264 calves with neonatal diarrhea
Background
The quantitative effect of strong electrolytes, unmeasured anions (UAs), pCO2, and plasma protein concentrations in determining plasma pH and bicarbonate (HCO3â) can be demonstrated using the physicochemical approach. Demeanor of calves with diarrhea is associated with acidemia, dehydration, and hyper-d-lactatemia.
Hypothesis
Unmeasured anions are a major factor influencing changes in plasma pH and HCO3â of calves with diarrhea and UAs and strong UAs, estimated by anion gap (AG) and strong ion gap (SIG), respectively, are more strongly associated with alteration of demeanor compared to other acidâbase variables.
Animals
A total of 264 calves with diarrhea from two data sets (DS1 and DS2).
Methods
Retrospective study. Forward stepwise regression was performed to determine the relationship between measured pH or HCO3â, and physicochemical variables. A two-way ANOVA was performed to investigate the association between acidâbase variables and attitude (bright, obtunded, and stuporous), posture (standing, sternal or lateral recumbency), and strength of suckling reflex (strong, weak, or absent).
Results
Increased strong UAs estimated by SIG was the most important contributor to changes in measured pH and HCO3â (DS1: r2 66 and 59%, DS2: 39 and 42%, P < .0001). SIG and AG were correlated to deteriorating calf demeanor for all three clinical scoring categories: attitude, posture, and suckle reflex (P < .0001).
Conclusion and Clinical Relevance
Elevated concentrations of strong UAs were the primary cause of acidemia and had an important influence on the demeanor of calves with diarrhea. These findings emphasize the importance of the calculation of UAs when evaluating acidâbase abnormalities in calves