Faster, more accurate, stack-flow measurements.

Exhaust flows from coal-fired electricity-generating plants are determined by averaging flue gas velocities measured at prescribed points in the stack cross section. These velocity measurements are made using EPA-approved differential pressure probes such as the 2-hole S-probe or the 5-hole spherical probe. Measurements using the more accurate 5-hole spherical probes require a time-consuming rotation (or nulling) of the probe to find the yaw angle. We developed a time-saving non-nulling technique using a spherical probe that measures all 3 components of velocity and therefore provides better accuracy than an S-probe. We compared the non-nulling technique with the EPA Method 2F nulling technique at both high (16 m/s) and low (7 m/s) loads in a coal-fired powerplant smokestack. Their excellent mutual agreement (within 0.3% of the flow) demonstrates that the non-nulling technique accurately measures flue gas flows.Implications: Accurate flow measurements are critical for quantifying the levels of greenhouse gases emitted from coal-fired power plant smokestacks. Flow measurement accuracy derives from the annual calibration of stack flow monitors. Calibrations are performed using EPA sanctioned pitot traverse methods called the flow relative accuracy test audit (RATA). This study demonstrates the viability of a new pitot traverse method, herein called the Non-Nulling Method. Testing in a coal-fired power plant stack showed that the new method is 5 times faster to implement than the most accurate EPA pitot traverse method (i.e., Method 2F), yet gives the same or better accuracy.

Synthetic MRI for Clinical Neuroimaging: Results of the Magnetic Resonance Image Compilation (MAGiC) Prospective, Multicenter, Multireader Trial.

BACKGROUND AND PURPOSE: Synthetic MR imaging enables reconstruction of various image contrasts from 1 scan, reducing scan times and potentially providing novel information. This study is the first large, prospective comparison of synthetic-versus-conventional MR imaging for routine neuroimaging. MATERIALS AND METHODS: A prospective multireader, multicase noninferiority trial of 1526 images read by 7 blinded neuroradiologists was performed with prospectively acquired synthetic and conventional brain MR imaging case-control pairs from 109 subjects (mean, 53.0 ± 18.5 years of age; range, 19-89 years of age) with neuroimaging indications. Each case included conventional T1- and T2-weighted, T1 and T2 FLAIR, and STIR and/or proton density and synthetic reconstructions from multiple-dynamic multiple-echo imaging. Images were randomized and independently assessed for diagnostic quality, morphologic legibility, radiologic findings indicative of diagnosis, and artifacts. RESULTS: Clinical MR imaging studies revealed 46 healthy and 63 pathologic cases. Overall diagnostic quality of synthetic MR images was noninferior to conventional imaging on a 5-level Likert scale (P < .001; mean synthetic-conventional, -0.335 ± 0.352; Δ = 0.5; lower limit of the 95% CI, -0.402). Legibility of synthetic and conventional morphology agreed in >95%, except in the posterior limb of the internal capsule for T1, T1 FLAIR, and proton-density views (all, >80%). Synthetic T2 FLAIR had more pronounced artifacts, including +24.1% of cases with flow artifacts and +17.6% cases with white noise artifacts. CONCLUSIONS: Overall synthetic MR imaging quality was similar to that of conventional proton-density, STIR, and T1- and T2-weighted contrast views across neurologic conditions. While artifacts were more common in synthetic T2 FLAIR, these were readily recognizable and did not mimic pathology but could necessitate additional conventional T2 FLAIR to confirm the diagnosis.

Antifertility and endocrine activities of gossypol in rodents.

Reversible male antifertility activity was obtained with orally administered gossypol acetic acid in rats at 20 mg/kg/day and in hamsters at 10 mg/kg/day but not in mice at dosages up to 40 mg/kg/day. An increased number of degenerating spermatocytes was found in the testicular tubular lumens of rats. Pigment-laden cells containing an intracytoplasmic lipofuscin-like material were noted in the testis and epididymal interstitium in rats and mice. Gossypol was also tested in the female for effects on ovulation and pregnancy. Gossypol did not inhibit ovulation in the rat at dosages up to 80 mg/kg/day but did cause 90% inhibition of pregnancy in mice treated with 80 mg/kg/day during the first two weeks of pregnancy. In several standard endocrine bioassays, gossypol did not demonstrate estrogenic, antiestrogenic, androgenic or antiandrogenic activities, but it did potentiate the androgenicity of methyltestosterone.

DRGs and hospital case records: implications for Medicare case mix accuracy.

As Medicare moves to DRG-based prospective payment, it is not clear whether the federal government has adequate data upon which to formulate DRG prices and assess hospital case mix. This study compares the Medicare case mix of Minneapolis-St. Paul hospitals based on the historical information submitted for billing purposes on the Medicare claim with the actual case mix of hospitals as described in the medical record chart. It was found that for the same patients, the DRG based on the claim matched the DRG on the medical record approximately half of the time. These "mismatches" resulted in a statistically significant understatement of hospitals' case mix, and have obvious implications for the setting of DRG prices and equitable hospital reimbursement.

Differences in inpatient resource use by type of health plan.

Approximately 50% of the annual increase in hospital costs comes from increased resource use per hospital admission. Health maintenance organizations (HMOs), given their fixed financial resources for patient care, have an incentive to constrain their enrollees' use of hospital resources. Our analysis investigates differences in length of stay, total charges, and the ancillary to total charge ratio for hospitalized patients in network HMOs, independent practice associations (IPAs), and fee-for-service (FFS) health plans in the Twin Cities from 1982 to 1984. Network HMO patients in several diagnostic categories are found to use significantly fewer resources, once hospitalized, than patients in either IPA or FFS plans. This difference may give network HMOs a competitive advantage in the market for health plans.

Neonatal response to control of noise inside the incubator.

PURPOSE: The purpose of this study was to test the effect of acoustical foam on the level of noise inside the incubator and examine neonatal response behaviors to changes in environmental noise. METHOD: The study used a repeated measure, within subject, comparative design. Data on 65 premature neonates were collected over a 14-month period at a large teaching hospital in Delaware. Sound levels, oxygen saturation, and infant states were measured and recorded during three study conditions: pre-study neonate in incubator, neonate in incubator with 5 x 5 x 1 inch acoustical foam pieces placed in each of four corners, and post-study recovery of neonate in incubator with foam removed. All state assessments were measured with oxygen saturation and sound level measurements every 2 minutes of the study for a total 40 minutes. FINDINGS: The findings demonstrate a significant treatment effect of acoustical foam on decreasing environmental noise measurements inside the incubator (p = 0.006). Findings also demonstrate significantly changed neonatal state response behaviors with decreasing environmental noise measurements inside the incubator (p = 0.00). CONCLUSIONS: The results of this study support the use of acoustical foam as one method of environmental noise management in the intensive care nursery. Because there was a significant correlation between higher noise levels and oxygen support therapy, the findings suggest that special nursing considerations should be taken when caring for ventilator-dependent infants. Noise control protocols should focus on essential environmental interventions for care of these infants.

A case management approach to immunizing patients at high risk for influenza.

The influenza season affects not only the people afflicted with influenza, but the healthcare system as a whole. An estimated dollar 12 billion is the annual cost to care for these patients. An existing problem is that although there is an immunization for influenza, many patients at high risk are not immunized. This article will describe an innovative program of a large Midwest suburban hospital to immunize patients at high risk.

Comparative aspects of contraceptive steroids--effects observed in beagle dogs.

The effects of oral contraceptives have been studied in the beagle bitch for periods up to 7 yr. High doses of these potent estrogen: progestogen (E:P) combinations have been shown to promote tumors in the mammary glands, smooth muscle of the tubular genitalia, and occasionally in the transitional epithelium of the neck/trigone area of the urinary bladder. The contraceptive formulations used in humans are balanced with an E:P ratio of about 1:5 to 1:80 to produce a desired decidual response in the uterus. The corresponding ratio for producing the decidual reaction in the dog is 1:1,000 to 1:3,000 with the result that the dog is grossly overdosed with estrogens when given the human formulation at the usual multiples of up to 25 times the human dose. Smooth muscle tumors of the tubular reproductive tract are common sequelae to estrogen overstimulation in the dog and are known to occur in other species, including the humans. The dog also has major differences in hormonal control and sensitivity when compared to humans. Progestogens stimulate synthesis and release of growth hormone (GH) in dogs which in turn is the major stimulant (with progestogens) of mammary growth and tumors. Evidence is accumulating which indicates that most if not all progestogens can produce mammary tumors in the dog if given by the correct route and at high enough dosage. In contrast, GH in humans is not increased nor does it have any significant mammotrophic role. Mammary tumors in dogs related to oral contraceptives are now widely considered to be irrelevant as a model or predictor for human tumors. Transitional cell tumors in the urinary bladder seem to be a species specific phenomenon seen on occasion in the dog, but not in the rat, monkey, or human. The usual location in the neck/trigone area may be related to the embryologic origin of this portion of the bladder, which derives from tissues more closely related to the genital organs than does the rest of the bladder.

The impact of health maintenance organizations and competition on hospitals in Minneapolis/St. Paul.

The Healthcare Educational and Research Foundation (HERF) in Minneapolis undertook a two-year research project to study the effects of health maintenance organizations (HMOs) and competition on the hospital industry in Minneapolis/St. Paul. This article summarizes HERF's major findings surrounding three key questions: (1) do the HMOs in Minneapolis/St. Paul use fewer hospital resources relative to conventional payers?; (2) do recent overall community trends in inpatient use suggest evidence of hospital utilization-reducing effects attributable to HMOs?; and (3) given the highly visible competitive process among Minneapolis/St. Paul providers, do hospital cost and revenue data suggest any evidence of cost-containment? The findings (based on data through 1982) indicate that for comparable patients, Twin Cities HMOs appear to use fewer medical care resources per hospitalized patient. There was, however, no clear evidence of community-wide, utilization-reducing effects directly attributable to the "competitive effect" of HMO introduction and development in the market. In addition, there was no empirical evidence that HMOs (which had enrolled 25 percent of the consumer market by 1982), or other large buyers of inpatient services, have selected hospitals on the basis of price as hypothesized by competition advocates.

Inpatient length of stay in Twin Cities health plans.

In this paper we examine the relationship between inpatient length of stay and the patient's type of health insurance. The data consist of discharges in seven diagnosis-related groups (DRGs) from community hospitals in Minneapolis and St. Paul during 1982. After controlling for the effects of the patient's age, sex, medical condition, and severity of illness, as well as the hospital's size, teaching and ownership status, and average annual occupancy rate, we must reject the null hypothesis that the patient's type of health plan is unrelated to inpatient length of stay in Twin Cities community hospitals. We find that, in most cases, patients in prepaid group practices and independent practice associations exhibit significantly shorter lengths of stay than similar patients in Blue Cross and commercial health insurance plans, while Medicare and Medicaid patients exhibit significantly longer lengths of stay than those of similar commercially insured patients.