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1.
Science ; 307(5713): 1226-36, 2005 Feb 25.
Article in English | MEDLINE | ID: mdl-15731439

ABSTRACT

Images acquired of Saturn's rings and small moons by the Cassini Imaging Science Subsystem (ISS) during the first 9 months of Cassini operations at Saturn have produced many new findings. These include new saturnian moons; refined orbits of new and previously known moons; narrow diffuse rings in the F-ring region and embedded in gaps within the main rings; exceptionally fine-scale ring structure in moderate- to high-optical depth regions; new estimates for the masses of ring-region moons, as well as ring particle properties in the Cassini division, derived from the analysis of linear density waves; ring particle albedos in select ring regions; and never-before-seen phenomena within the rings.

2.
Science ; 307(5713): 1237-42, 2005 Feb 25.
Article in English | MEDLINE | ID: mdl-15731440

ABSTRACT

The Cassini Imaging Science Subsystem acquired high-resolution imaging data on the outer Saturnian moon, Phoebe, during Cassini's close flyby on 11 June 2004 and on Iapetus during a flyby on 31 December 2004. Phoebe has a heavily cratered and ancient surface, shows evidence of ice near the surface, has distinct layering of different materials, and has a mean density that is indicative of an ice-rock mixture. Iapetus's dark leading side (Cassini Regio) is ancient, heavily cratered terrain bisected by an equatorial ridge system that reaches 20 kilometers relief. Local albedo variations within and bordering Cassini Regio suggest mass wasting of ballistically deposited material, the origin of which remains unknown.


Subject(s)
Saturn , Extraterrestrial Environment , Geologic Sediments , Ice , Spacecraft , Water
3.
Science ; 307(5713): 1243-7, 2005 Feb 25.
Article in English | MEDLINE | ID: mdl-15731441

ABSTRACT

The Cassini Imaging Science Subsystem (ISS) began observing Saturn in early February 2004. From analysis of cloud motions through early October 2004, we report vertical wind shear in Saturn's equatorial jet and a maximum wind speed of approximately 375 meters per second, a value that differs from both Hubble Space Telescope and Voyager values. We also report a particularly active narrow southern mid-latitude region in which dark ovals are observed both to merge with each other and to arise from the eruptions of large, bright storms. Bright storm eruptions are correlated with Saturn's electrostatic discharges, which are thought to originate from lightning.


Subject(s)
Saturn , Atmosphere , Extraterrestrial Environment , Spacecraft , Wind
4.
J Health Care Finance ; 28(1): 25-38, 2001.
Article in English | MEDLINE | ID: mdl-11669291

ABSTRACT

The purpose of this study is to determine the extent to which health maintenance organization (HMO) penetration within the public hospitals' market area affects the financial performance and viability of these institutions, relative to private hospitals. Hospital- and market-specific measures are examined in a fully interacted model of over 2,300 hospitals in 321 metropolitan statistical areas (MSAs) in 1995. Although hospitals located in markets with higher HMO penetration have lower financial performance as reflected in revenues, expenses and operating margin, public hospitals are not more disadvantaged than other hospitals by managed care.


Subject(s)
Financial Management, Hospital , Health Maintenance Organizations/statistics & numerical data , Hospitals, Private/economics , Hospitals, Public/economics , Catchment Area, Health , Health Care Sector , Health Services Research , Income , Models, Econometric , United States
7.
Med Care Res Rev ; 57 Suppl 2: 53-71, 2000.
Article in English | MEDLINE | ID: mdl-11105506

ABSTRACT

This article uses a 4-pronged statistical approach to examine the impact of a mental health carve-out at a major employer. To examine net financial impact of the carve-out, the authors perform a pre-post, multivariate regression analysis of changes in costs. Using a random-effects model, the authors explore the ultimate financial impact of the carve-out for patients and for the firm. Using a multinomial logistic regression, they examine differing program effects by intensity of use. A fixed-effects negative binomial regression models the episodic nature of outpatient care, controlling for patient-specific unobserved characteristics that influence health care utilization. The carve-out slightly reduced overall mental health costs and utilization while expanding entry-level access to routine services. At the same time, the specific carve-out shifted financial burdens from the firm onto high-utilization patients. Therefore, this carve-out appears poorly suited to the care of individuals experiencing severe and debilitating psychiatric disorders.


Subject(s)
Diffusion of Innovation , Health Benefit Plans, Employee/organization & administration , Health Services Research/organization & administration , Insurance, Psychiatric , Mental Health Services/economics , Preferred Provider Organizations/organization & administration , Adult , California , Female , Health Care Costs/statistics & numerical data , Health Policy , Health Services Accessibility/organization & administration , Humans , Logistic Models , Male , Middle Aged , Multivariate Analysis , Program Evaluation
8.
J Behav Health Serv Res ; 26(4): 381-9, 1999 Nov.
Article in English | MEDLINE | ID: mdl-10565099

ABSTRACT

This study examines the effects of a mental health carve-out on a sample of continuously enrolled employees (N = 1,943) over a four-year time frame (1990-1994). The article presents a health care services utilization model of the effect of the carve-out on outpatient mental health use, cost, and source of payment in the three years post implementation relative to the year prior to the carve-out model. In the first three years of the carve-out, the likelihood of employees seeking mental health care increased in significant part because of the carve-out. For the outpatient mental health services user, the carve-out was not associated with the level of mental health services received. The carve-out was significantly associated over time with a reduction in the patient's and employer's mental health costs. This effect was more pronounced in the second and third years of the carve-out. The article explores the policy implications of these and other findings.


Subject(s)
Behavior Therapy/economics , Health Benefit Plans, Employee/economics , Mental Health Services/economics , Preferred Provider Organizations/economics , Adult , Cost-Benefit Analysis , Female , Health Benefit Plans, Employee/statistics & numerical data , Humans , Male , Mental Health Services/statistics & numerical data , Middle Aged , Preferred Provider Organizations/statistics & numerical data , United States
12.
Med Care Res Rev ; 56 Suppl 2: 37-59, 1999.
Article in English | MEDLINE | ID: mdl-10327823

ABSTRACT

To control the rise in expenditures and to increase access to mental health and substance abuse (MH/SA) services, a growing number of employers and states are implementing a "carve-out." Under this arrangement, the sponsor separates insurance benefits by disease or condition, service category, or population and contracts separately for the management of care and/or associated risks. A carve-out allows a unique set of managed care techniques to be applied to a subset of particularly costly or complex benefits. This article describes various carve-out models, discusses the potential advantages and disadvantages of a full carve-out, and summarizes recent public and private sector research regarding the strategy's effects on access and use, cost savings and shifting, and quality of care. It concludes by discussing approaches to the assessment and monitoring of the processes and outcomes associated with a MH/SA carve-out.


Subject(s)
Contract Services/economics , Health Benefit Plans, Employee/economics , Managed Care Programs/organization & administration , Mental Health Services/organization & administration , Cost Control , Disease Management , Employer Health Costs/trends , Health Services Accessibility , Humans , Managed Care Programs/statistics & numerical data , Medicaid/economics , Mental Health Services/statistics & numerical data , Product Line Management , United States
18.
J Healthc Manag ; 43(1): 3-5, 1998.
Article in English | MEDLINE | ID: mdl-10178791
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