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In 2008, the Centers for Medicare and Medicaid Services (CMS) stopped reimbursing for hospital-acquired conditions (HACs) not present on admission (POA). We sought to understand why this policy did not impact central line–associated bloodstream infection (CLABSI) and catheter-associated urinary tract infection (CAUTI) trends.
Retrospective cohort study.
Acute-care hospitals in the United States.
Fee-for-service Medicare patients discharged January 1, 2007, through December 31, 2011.
Using inpatient Medicare claims data, we analyzed billing practices before and after the HAC policy was implemented, including the use and POA designation of codes for CLABSI or CAUTI. For the 3-year period following policy implementation, we determined the impact on diagnosis-related groups (DRG) determining reimbursement as well as hospital characteristics associated with the reimbursement impact.
During the study period, 65,205,607 Medicare fee-for-service hospitalizations occurred at 3,291 acute-care, nonfederal US hospitals. Based on coding, CLABSI and CAUTI affected 0.23% and 0.06% of these hospitalizations, respectively. In addition, following the HAC policy, 82% of the CLABSI codes and 91% of the CAUTI codes were marked POA, which represented a large increase in the use of this designation. Finally, for the small numbers of CLABSI and CAUTI coded as not POA, financial impacts were detected on only 0.4% of the hospitalizations with a CLABSI code and 5.7% with a CAUTI code.
Part of the reason the HAC policy did not have its intended impact is that billing codes for CLABSI and CAUTI were rarely used, were commonly listed as POA in the postpolicy period, and infrequently impacted hospital reimbursement.
In 2012, the Centers for Medicare and Medicaid Services expanded a 2008 program that eliminated additional Medicare payment for mediastinitis following coronary artery bypass graft (CABG) to include Medicaid. We aimed to evaluate the impact of this Medicaid program on mediastinitis rates reported by the National Healthcare Safety Network (NHSN) compared with the rates of a condition not targeted by the program, deep-space surgical site infection (SSI) after knee replacement.
Interrupted time series with comparison group.
We included surveillance data from nonfederal acute-care hospitals participating in the NHSN and reporting CABG or knee replacement outcomes from January 2009 through June 2017. We examined the Medicaid program’s impact on NHSN-reported infection rates, adjusting for secular trends. The data analysis used generalized estimating equations with robust sandwich variance estimators.
During the study period, 196 study hospitals reported 273,984 CABGs to the NHSN, resulting in 970 mediastinitis cases (0.35%), and 294 hospitals reported 555,395 knee replacements, with 1,751 resultant deep-space SSIs (0.32%). There was no significant change in incidence of either condition during the study. Mediastinitis models showed no effect of the 2012 Medicaid program on either secular trend during the postprogram versus preprogram periods (P=.70) or an immediate program effect (P=.83). Results were similar in sensitivity analyses when adjusting for hospital characteristics, restricting to hospitals with consistent NHSN reporting or incorporating a program implementation roll-in period. Knee replacement models also showed no program effect.
The 2012 Medicaid program to eliminate additional payments for mediastinitis following CABG had no impact on reported mediastinitis rates.
We compared the calculation performance of cosmological N-body simulations with and without GRAPE-4. A modified Barnes-Hut treecode was used for these simulations. GRAPE(GRAvity piPE) is a special-purpose computer for gravitational N-body simulations. The newest hardware GRAPE-4 achieved a quite high peak performance (1.08 Tflops). In cosmological N-body simulations, a large number of particles is required and fast algorithms such as Barnes-Hut treecode or P3M/PM are usually used. GRAPE-4 can accelearte such algorithms. In paticular, the PCI interface recently completed allows us to use fast host computer, thus it improved the performance of these fast algorithms. Figure 1 shows the CPU time per one timestep as functions of force calculation error for both systems with and without GRAPE-4.
Since the discovery of fading X-rays from Gamma-Ray Bursts (GRBs) with BeppoSAX (Piro et al. 1997, Costa et al. 1997), world-wide follow-up observations in optical band have achieved the fruitful results. The case of GRB 970228, there was an optical transient, coincides with the BeppoSAX position and faded (Paradijs et al. 1997, Sahu et al. 1997). These optical observations also confirmed the extended component, which was associated with the optical transient. The new transient are fading with a power-law function in time and the later observation of HST confirmed the extended emission is stable (Fruchter et al. 1997). This extended object seems to be a distant galaxy and strongly suggests to be the host.
Here we present a very short review of the ASCA observation campaign of the enigmatic galactic jet system SS433. The campaign started in 1994 just after the launch, and ended in 1996. Various phases of the 162.5-day precession and 13-day orbital motion were sampled. With ASCA, the Doppler-shifted pairs from various ion species from Si to Ni were resolved for the first time (Kotani et al. 1994). The Doppler-shift parameters were determined with an accuracy comparable to optical spectroscopy (Kawai 1995). No velocity gradient was found between the X-ray emission region of the jet and the optical. The distance between them was constrained to be less than 1015 cm. Line intensity ratios of Fe XXVI/Fe XXV give the base temperature of the jet to be 20 keV (Kotani et al. 1996). The variation of the apparent base temperature of the jet can be explained in terms of the partial occultation of the jet by a precessing accretion disk (Kotani et al. 1997a). From the variation, the disk radius and the disk height in unit of the X-ray jet length were estimated to be 0.23 ± 0.10 and 0.0232 ± 0.0049, respectively. (These are an improved version of the values in Kotani et al. (1997a).) SS433 is also known as an eclipsing binary. Because the emission from each jet with ASCA, it is possible to know how much of which jet is occulted by the companion star during an eclipse. Relative size of the companion star gives Roche lobe size and thus mass ratio MX/MC = 0.22+0.09-0.16 (Kotani 1997b). With the help of Doppler modulation, compact star mass is constrained. However, the values of Doppler modulation reported from optical observations largely scatters. D'Odorico et al. (1991) reported 112 km s−1 and this gives MX = 0.68+0.43-0.53 M⊙, i.e., a white dwarf, while Fabrika and Bychkova (1990) reported 175 km s−1, which gives 2.6+1.6-2.0 M⊙. (This error includes systematic errors of the X-ray data, and will be reduced in future analysis.) On the other hand, the absolute size of the system were determined with a satisfactory precision. For example, the X-ray jet length was determined to be 2×1013 cm, ten times larger than previous estimations (Kotani et al. 1997c). Other physical parameters of the jet can be derived from the X-ray jet length. Mass outflow rate and the kinetic luminosity of both jet were determined to be 8 × 10−6 M⊙ yr−1 and 1.6 × 1040 erg s−1 (Kotani et al. 1997d), implicating a highly super critical accretion. Most of these values are first precise measurements and/or “radical” revisions of previous estimations. The new picture of SS433 drawn here is far stormy and highly energetic.
We report on the spectral and temporal properties of the 50 ms pulsar PSR B0540–69 using ASCA archival data obtained during 1993 to 1995. From the spectral analysis it was found that the spectra of the whole (nebular and pulsed) emission and pulsed emission in the range 1-10 keV can be represented by a single power law of photon index, Γ = 2.00 ± 0.02 and Γpulsed = 1.7 ± 0.3 respectively. The parameters for pulse frequency change during 1993-1995 were obtained using the 9 pulse frequency measurements with ASCA. The parameters derived from the ASCA observations are consistent with the previous measurements, suggesting high stability of this pulsar, ΔΩ/Ω ≲ 0.5 × 10−7 over the past 10 years. These results confirm similarity of this pulsar with the Crab pulsar.
We propose an X-ray all sky monitor for Japanese Experimental Module (JEM) on the space station. Considering practical circumstances, we show as a case study that the all sky monitor with slit hole cameras is most promising for monitoring the short-term and long-term X-ray transients. We call this all sky monitor as MAXI (Monitor of All-sky X-ray Image). Position determination of gamma-ray bursts could be achieved with accuracy less than one degree observing the X-ray component of the burst. Weak X-ray sources such as active galactic nuclei could be also monitored with time resolution less than one day. The X-ray all sky monitor will work to discover X-ray novae and transient phenomena and give us the alarm for further detailed observations. The obtained data will be also used for archival study.
SS 433 has been observed with ASCA for three years since the launch in 1993. The excellent energy resolution of ASCA revealed the Doppler-shifted emission lines from the both jets, though it had been generally accepted that the X-ray emitting region of the receding jet is hidden behind the accretion disk. Thus the estimation on the properties of the X-ray jet, such as length, temperature, and mass outflow rate, should be revised in accordance with the ASCA data. Modeling the jet as a radiating ballistic plasma, we determined these quantities. It is also tried to determine the mass of the system from a data covering an eclipse.
The High Energy Transient Explorer 2 is a small scientific satellite designed to detect and localize gamma-ray bursts (GRBs). The coordinates of GRBs detected by HETE-2 will be distributed to interested ground-based observers within seconds of burst detection, thereby allowing detailed observations of the initial phases of GRBs. HETE-2 was launched successfully on October 9, 2000. The GRB positions will start to be delivered after a few months of the complete testing and calibration of the spacecraft system and the science instruments.
The kinetics of Ge lateral overgrowth on SiO2 with line-shaped Si seeds is examined. The growth process is described by the difference between the growth rates of Ge on (100) planes (GR100) and <311> facets (GR311). The theoretical calculations well reproduce the growth kinetics. It is shown that narrowing the line-seeds helps Ge coalescence and flat film formation.
In October 2008, Medicare ceased additional payment for hospital-acquired conditions not present on admission. We evaluated the policy’s differential impact in hospitals with high vs low operating margins. Medicare’s payment policy may have had an impact on reducing central line–associated bloodstream infections in hospitals with low operating margins.
Infect. Control Hosp. Epidemiol. 2015;37(1):100–103
The 2008 Centers for Medicare & Medicaid Services hospital-acquired conditions policy limited additional payment for conditions deemed reasonably preventable.
To examine whether this policy was associated with decreases in billing rates for 2 targeted conditions, vascular catheter-associated infections (VCAI) and catheter-associated urinary tract infections (CAUTI).
Adult Medicare patients admitted to 569 acute care hospitals in California, Massachusetts, or New York and subject to the policy.
We used an interrupted times series design to assess whether the hospital-acquired conditions policy was associated with changes in billing rates for VCAI and CAUTI.
Before the policy, billing rates for VCAI and CAUTI were increasing (prepolicy odds ratio per quarter for VCAI, 1.17 [95% CI, 1.11–1.23]; for CAUTI, 1.19 [1.16–1.23]). The policy was associated with an immediate drop in billing rates for VCAI and CAUTI (odds ratio for change at policy implementation for VCAI, 0.75 [95% CI, 0.69–0.81]; for CAUTI, 0.87 [0.79–0.96]). In the postpolicy period, we observed a decreasing trend in the billing rate for VCAI and a leveling-off in the billing rate for CAUTI (postpolicy odds ratio per quarter for VCAI, 0.98 [95% CI, 0.97–0.99]; for CAUTI, 0.99 [0.97–1.00]).
The Centers for Medicare & Medicaid Services hospital-acquired conditions policy appears to have been associated with immediate reductions in billing rates for VCAI and CAUTI, followed by a slight decreasing trend or leveling-off in rates. These billing rates, however, may not correlate with changes in clinically meaningful patient outcomes and may reflect changes in coding practices.
Infect. Control Hosp. Epidemiol. 2015;36(8):871–877
Policymakers may wish to align healthcare payment and quality of care while minimizing unintended consequences, particularly for safety net hospitals.
To determine whether the 2008 Centers for Medicare and Medicaid Services Hospital-Acquired Conditions policy had a differential impact on targeted healthcare-associated infection rates in safety net compared with non–safety net hospitals.
Interrupted time-series design.
SETTING AND PARTICIPANTS
Nonfederal acute care hospitals that reported central line–associated bloodstream infection and ventilator-associated pneumonia rates to the Centers for Disease Control and Prevention’s National Health Safety Network from July 1, 2007, through December 31, 2013.
We did not observe changes in the slope of targeted infection rates in the postpolicy period compared with the prepolicy period for either safety net (postpolicy vs prepolicy ratio, 0.96 [95% CI, 0.84–1.09]) or non–safety net (0.99 [0.90–1.10]) hospitals. Controlling for prepolicy secular trends, we did not detect differences in an immediate change at the time of the policy between safety net and non–safety net hospitals (P for 2-way interaction, .87).
The Centers for Medicare and Medicaid Services Hospital-Acquired Conditions policy did not have an impact, either positive or negative, on already declining rates of central line–associated bloodstream infection in safety net or non–safety net hospitals. Continued evaluations of the broad impact of payment policies on safety net hospitals will remain important as the use of financial incentives and penalties continues to expand in the United States.
We developed a tunnel-current based identification method by using nano-gap integrated devices. We performed electrical measurements for mono-nucleotide and oligo-nucleotide during its translocation of molecules between the nano-gap. Based on this determined electrical conductivity for single-nucleotides, we electrically identify the base-type in oligonucleotides, and found that this time-profiles represents the molecular translocation behaviors inside nano-gap. This method could be a promising for an electrical nucleotide sequencing methodology with label-free, high-speed, and low-cost.
Limited studies exist regarding whether incorporating micronutrient supplements during tuberculosis (TB) treatment may improve cell-mediated immune response. We examined the effect of micronutrient supplementation on lymphocyte proliferation response to mycobacteria or T-cell mitogens in a randomized trial conducted on 423 patients with pulmonary TB. Eligible participants were randomly assigned to receive a daily dose of micronutrients (vitamins A, B-complex, C, E, and selenium) or placebo at the time of initiation of TB treatment. We found no overall effect of micronutrient supplements on lymphocyte proliferative responses to phytohaemagglutinin or purified protein derivatives in HIV-negative and HIV-positive TB patients. Of HIV-negative TB patients, the micronutrient group tended to show higher proliferative responses to concanavalin A than the placebo group, although the clinical relevance of this finding is not readily notable. The role of nutritional intervention in this vulnerable population remains an important area of future research.
Monitor of All-sky X-ray Image (MAXI) on board International Space Station is capable of
observing gamma-ray bursts (GRBs) and sending notices of GRBs or other transient events,
using real time connection to the ground. MAXI observed 32 GRBs or short X-ray transients
as of the end of September 2012. Among them, eleven events were simultaneously detected by
other satellites. The observed rate of the MAXI GRBs is about one event per month. This
rate is comparable to a past observation with larger effective area and larger field of
view. The fact indicates that MAXI has better sensitivity to observe GRBs because of low
background. The distribution of the spectral hardness of MAXI GRBs is similar to the
results of a past instrument, which is sensitive to similar energy range.
We have investigated electronic band-gap states in AlGaN/GaN hetero-structures with different growth conditions of GaN buffer layers from a viewpoint of Carbon impurity incorporation into GaN, using photoluminescence (PL), capacitance-voltage (C-V) and steady-state photo-capacitance spectroscopy (SSPC) techniques. The Carbon incorporation was found to be enhanced with decreasing the growth temperature of the GaN buffer layer between 1120 and 1170 °C. Acting in concert, three specific deep levels located at ~2.07, ~2.70, and ~3.23 eV below the conduction band were found to become dense significantly at the low growth temperature. Therefore, these levels are probably attributable to Ga vacancies and/or Carbon acceptors produced by the Carbon impurity incorporation, and are likely in conjunction with each other.