367 research outputs found
Comparison of the poleward transport of ozone in the Northern and Southern Hemispheres
Six and one-half years of ozone data and temperature data are used to extend Geller et al.'s (1988) study comparing the transport of ozone to high latitudes in the Northern and Southern Hemispheres. In this earlier study, it was pointed out that the poleward transport of ozone varies annually in the Northern Hemisphere but has a marked semiannual behavior in the Southern Hemisphere. This earlier study covered the period from December 1978 to November 1982. Two and one-half additional years have now been analyzed so that the analysis now extends to July 1986. With this extended data set, the maximum rate of increase in total ozone is seen to occur in January in the Northern Hemisphere for all of the years investigated. In the Southern Hemisphere, the maximum rate of increase is seen in September for almost all of the years with a secondary maximum in the rate of increase in total ozone often being seen during March-April period. The nature of the seasonal variation in total ozone is found to be much more variable in the Southern Hemisphere than in the Northern Hemisphere
Residual circulations calculated from satellite data: Their relations to observed temperature and ozone distributions
Monthly mean residual circulations were calculated from eight years of satellite data. The diabatic circulation is usually found to give a good approximation to the residual circulation, but this is not always the case. In particular, an example is shown at 60 deg S and 30 mbar where the diabatic and residual circulations show very different annual variations. Correlations between the vertical component of the residual circulation and temperature and ozone were computed. The computations indicate that yearly variations of temperatures in the tropics are under radiative control, except during stratospheric warmings. Interannual variations in seasonal mean temperatures are shown to be under dynamical control everywhere. Correlations between seasonal means of the vertical component of the residual circulation and ozone mixing ratios are consistent with what would be expected from the ozone variations being due to differences in the ozone transport, although transport effects cannot easily be distinguished from photochemical effects above the altitude of the ozone mixing ratio peak. Finally, variations in total ozone are examined in comparison with residual circulation variations. A one to two month phase lag is seen in the annual variation in the total ozone at 60 deg N with respect to the maximum downward residual motions. This phase lag is greater at 60 deg N than at 60 deg S. There is evidence at 60 deg S of a greater downward trend in the mean zonal ozone maxima than there is in the minima. A decreasing trend in the maximum descending motion is seen to accompany the ozone trend at 60 deg S
Stratospheric General Circulation with Chemistry Model (SGCCM)
In the past two years constituent transport and chemistry experiments have been performed using both simple single constituent models and more complex reservoir species models. Winds for these experiments have been taken from the data assimilation effort, Stratospheric Data Analysis System (STRATAN)
Comparison of Surface Area across the Allograft-Host Junction Site Using Conventional and Navigated Osteotomy Technique.
Bulk allograft reconstruction plays an important role in limb-salvage surgery; however, non-union has been reported in up to 27% of cases. The purpose of this study is to quantify average surface contact areas across simulated intraoperative osteotomies using both free-hand and computer-assisted navigation techniques. Pressure-sensitive paper was positioned between two cut ends of a validated composite sawbone and compression was applied using an eight-hole large fragment dynamic compression plate. Thirty-two samples were analyzed for surface area contact to determine osteotomy congruity. Mean contact area using the free-hand osteotomy technique was equal to 0.21 square inches. Compared with a control of 0.69 square inches, average contact area was found to be 30.5% of optimal surface contact. Mean contact area using computer-assisted navigation was equal to 0.33 square inches. Compared with a control of 0.76 square inches, average contact area was found to be 43.7% of optimal surface contact. Limited contact achieved using standard techniques may play a role in the high rate of observed non-union, and an increase in contact area using computer-assisted navigation may improve rates of bone healing. The development of an oncology software package and navigation hardware may serve an important role in decreasing non-union rates in limb salvage surgery
L ennox‐ G astaut syndrome of unknown cause: Phenotypic characteristics of patients in the E pilepsy P henome/ G enome P roject
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/101778/1/epi12395.pd
Bright Variable Stars in NGC 6819 - An Open Cluster in the Kepler Field
We describe a variability study of the moderately old open cluster NGC 6819.
We have detected 4 new detached eclipsing binaries near the cluster turnoff
(one of which may be in a triple system). Several of these systems should be
able to provide mass and radius information, and can therefore constrain the
age of the cluster. We have also newly detected one possible detached binary
member about 3.5 magnitudes below the turnoff. One EW-type binary (probably not
a cluster member) shows unusually strong night-to-night light curve variations
in sets of observations separated by 8 years. According to the best current
information, the three brightest variables we detected (2 of them new) are
cluster members, making them blue stragglers. One is a delta Scu pulsating
variable, one is a close but detached binary, and the third contains a detached
short period binary that shows total eclipses. In each case, however, there is
evidence hinting that the system may have been produced through the interaction
of more than two stars.Comment: 33 pages, 15 figures, accepted to A
Development And Preliminary Psychometric Evaluation of the Children\u27s Saving Inventory
This study reports on the development and initial psychometric properties of the Children\u27s Saving Inventory (CSI), a parent-rated measure designed to assess child hoarding behaviors. Subjects included 123 children and adolescents diagnosed with primary Obsessive-Compulsive Disorder (OCD) and their parents. Trained clinicians administered the Children\u27s Yale-Brown Obsessive-Compulsive Scale (CY-BOCS), items assessing Family Accommodation and the Clinical Global Impressions-Severity index. Parents completed the CSI, Child Obsessive-Compulsive Impact Scale (COIS)-Parent Version and Child Behavior Checklist. Youth completed the COIS-Child Version, Obsessive-Compulsive Inventory Child Version (OCI-CV), Multidimensional Anxiety Scale for Children, and Children\u27s Depression Inventory-Short Form. A four factor solution was identified; factors were named Discarding, Clutter, Acquisition, and Distress/Impairment. Internal consistency for the CSI Total and factor scores were good. One-week test-retest reliability (n = 31) from a random subsample was excellent. Known groups validity was supported vis-à-vis higher CSI scores for those endorsing hoarding on the CY-BOCS Symptom Checklist. Convergent and discriminant validity was evidenced by weak relationships with OCI-CV Checking and Contamination factors but strong relationships with the OCI-CV Hoarding factor and with hoarding obsession/compulsions on the CY-BOCS. These findings provide initial support for the reliability and validity of the CSI for the assessment of hoarding behaviors among youth with OCD. Future studies are needed to extend these findings to non-OCD samples of youth
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