Robotic versus laparoscopic colectomy RAWLINGS, A. L; WOODLAND, J. H; VEGUNTA, R. K ...
Surgical endoscopy,
10/2007, Letnik:
21, Številka:
10
Journal Article
Recenzirano
This study compared the experience and cost of the DaVinci Robotic system and laparoscopy for colon resections.
For this study, 30 consecutive robotic and 27 consecutive laparoscopic colectomies were ...divided into right and sigmoid colectomies for analysis. Comparisons included indications for surgery, gender, age, body mass index (BMI), estimated blood loss (EBL), length of operation, length of hospital stay (LOS), complications, operating room (OR) cost, OR personnel cost, OR supply cost, OR time cost, and total hospital cost.
The comparison groups were similar in indications for surgery, gender, age, BMI, EBL, and LOS. The right colectomies included 17 robotic and 15 laparoscopic procedures. An intracorporeal anastomosis was performed in the robotic cases, and an extracorporeal anastomosis was performed in the laparoscopic cases. The total case time was 218.9 min for the robotic and 169.2 min for the laparoscopic procedures (p = 0.002). The total hospital cost was $9,255 for the robotic and $8,073 for the laparoscopic procedures (p = 0.430). The total OR cost was $5,823 for the robotic and $4,339 for the laparoscopic procedures (p < 0.000). The sigmoid colectomies included 13 robotic and 12 laparoscopic procedures. The robotic and laparoscopic cases were managed in similar sequence. The total case time was 225.2 min for the robotic and 199.4 min for the laparoscopic procedures (p = 0.128). The total hospital cost was $12,335 for the robotic and $10,697 for the laparoscopic procedures (p = 0.735). The total OR cost was $6,059 for the robotic and $4,974 for the laparoscopic procedures (p = 0.068). The complications in the robotic groups were more numerous, but were not attributable to equipment.
The comparison groups were similar. The robotic cases were significantly longer for right colectomies because of the intracorporeal anastomosis instead of the extracorporeal anastomosis performed in the laparoscopy cases. Every cost category was higher for the robotic cases. The right colectomies showed significant increases in total OR cost, OR personnel cost, OR supply cost, and OR time cost. The sigmoid colectomies had significant increases in OR personnel cost and OR supply cost. The total hospital cost was higher for the robotic groups, but the difference was not statistically significant.
The measurement of OH reactivity, the inverse of the OH lifetime, provides a powerful tool to investigate atmospheric photochemistry. A new airborne OH reactivity instrument was designed and deployed ...for the first time on the NASA DC-8 aircraft during the second phase of Intercontinental Chemical Transport Experiment-B (INTEX-B) campaign, which was focused on the Asian pollution outflow over Pacific Ocean and was based in Hawaii and Alaska. The OH reactivity was measured by adding OH, generated by photolyzing water vapor with 185 nm UV light in a moveable wand, to the flow of ambient air in a flow tube and measuring the OH signal with laser induced fluorescence. As the wand was pulled back away from the OH detector, the OH signal decay was recorded; the slope of −Δln(signal)/Δ time was the OH reactivity. The overall absolute uncertainty at the 2σ confidence levels is about 1 s−1 at low altitudes (for decay about 6 s−1), and 0.7 s−1 at high altitudes (for decay about 2 s−1). From the median vertical profile obtained in the second phase of INTEX-B, the measured OH reactivity (4.0±1.0 s−1) is higher than the OH reactivity calculated from assuming that OH was in steady state (3.3±0.8 s−1), and even higher than the OH reactivity that was calculated from the total measurements of all OH reactants (1.6±0.4 s−1). Model calculations show that the missing OH reactivity is consistent with the over-predicted OH and under-predicted HCHO in the boundary layer and lower troposphere. The over-predicted OH and under-predicted HCHO suggest that the missing OH sinks are most likely related to some highly reactive VOCs that have HCHO as an oxidation product.
We propose a large-area, cost-effective muon telescope detector (MTD) at mid-rapidity for the solenoidal tracker at the RHIC (STAR) and for the next generation of detectors at a possible electron-ion ...collider. We utilize large multi-gap resistive plate chambers with long readout strips (long-MRPC) in the detector design. The results from cosmic ray and beam tests show that the intrinsic timing and spatial resolution for a long-MRPC are 60-70 ps and ~1 cm, respectively. The performance of the prototype muon telescope detector at STAR indicates that muon identification at a transverse momentum of a few GeV/c can be achieved by combining information from track matching with the MTD, ionization energy loss in the time projection chamber and time-of-flight measurements. A primary muon over secondary muon ratio of better than 1/3 can be achieved. This provides a promising device for future quarkonium programs and primordial dilepton measurements at the RHIC. Simulations of the muon efficiency, the signal-to-background ratio of J/psi, the separation of 1S from 2S+3S states and the electron-muon correlation from charm pair production in the RHIC environment are presented.
Nitrogen oxides (NOx≡ NO + NO2) are of central importance for air quality, climate forcing, and nitrogen deposition to ecosystems. The Geostationary Environment Monitoring Spectrometer (GEMS) is now ...providing hourly NO2 satellite observations over East Asia, offering the first direct measurements of NO2 diurnal variation from space to guide understanding of NOx emissions and chemistry. The NO2 retrieval requires independent vertical profile information from a chemical transport model (CTM) to compute the air mass factor (AMF) that relates the NO2 column measured along the line of sight to the NO2 vertical column. Here, we use aircraft observations from the Korea-United States Air Quality (KORUS-AQ) campaign over the Seoul metropolitan area (SMA) and around the Korean Peninsula in May–June 2016 to better understand the factors controlling the NO2 vertical profile, its diurnal variation, the implications for the AMFs, and the ability of the GEOS-Chem CTM to compute the NO2 vertical profiles used for AMFs. Proper representation of oxidant chemistry is critical for the CTM simulation of NO2 vertical profiles and is achieved in GEOS-Chem through new model developments, including aerosol nitrate photolysis, reduced uptake of hydroperoxy (HO2) radicals by aerosols, and accounting for atmospheric oxidation of volatile chemical products (VCPs). We find that the tropospheric NO2 columns measured from space in the SMA are mainly contributed by the planetary boundary layer (PBL) below 2 km altitude, reflecting the highly polluted conditions. Repeated measurements of NO2 vertical profiles over the SMA at different times of day show that diurnal change in mixing depth affecting the NO2 vertical profile induces a diurnal variation in AMFs of comparable magnitude to the diurnal variation in the NO2 column. GEOS-Chem captures this diurnal variation in AMFs and more generally the variability in the AMFs for the KORUS-AQ NO2 vertical profiles (2.7 % mean bias, 7.6 % precision), with some outliers in the morning due to errors in the timing of mixed-layer growth.
We report new STAR measurements of the single-spin asymmetries AL for W+ and W− bosons produced in polarized proton-proton collisions at s=510 GeV as a function of the decay-positron and ...decay-electron pseudorapidity. The data were obtained in 2013 and correspond to an integrated luminosity of 250 pb−1. The results are combined with previous results obtained with 86 pb−1. A comparison with theoretical expectations based on polarized lepton-nucleon deep-inelastic scattering and prior polarized proton-proton data suggests a difference between the u¯ and d¯ quark helicity distributions for 0.05<x<0.25. In addition, we report new results for the double-spin asymmetries ALL for W±, as well as AL for Z/γ* production and subsequent decay into electron-positron pairs.
Parity (P)-odd domains, corresponding to nontrivial topological solutions of the QCD vacuum, might be created during relativistic heavy-ion collisions. These domains are predicted to lead to charge ...separation of quarks along the orbital momentum of the system created in noncentral collisions. To study this effect, we investigate a three-particle mixed-harmonics azimuthal correlator which is a P-even observable, but directly sensitive to the charge-separation effect. We report measurements of this observable using the STAR detector in Au+Au and Cu+Cu collisions at {radical}s{sub NN} = 200 and 62 GeV. The results are presented as a function of collision centrality, particle separation in rapidity, and particle transverse momentum. A signal consistent with several of the theoretical expectations is detected in all four data sets. We compare our results to the predictions of existing event generators and discuss in detail possible contributions from other effects that are not related to P violation.
Observations of a comprehensive suite of inorganic and organic trace gases, including non-methane hydrocarbons (NMHCs), halogenated organics and oxygenated volatile organic compounds (OVOCs), ...obtained from the NASA DC-8 over Canada during the ARCTAS aircraft campaign in July 2008 illustrate that convection is important for redistributing both long- and short-lived species throughout the troposphere. Convective outflow events were identified by the elevated mixing ratios of organic species in the upper troposphere relative to background conditions. Several dramatic events were observed in which isoprene and its oxidation products were detected at hundreds of pptv at altitudes higher than 8 km. Two events are studied in detail using detailed experimental data and the NASA Langley Research Center (LaRC) box model. One event had no lightning NOx (NO + NO2) associated with it and the other had substantial lightning NOx (LNOx > 1 ppbv). When convective storms transport isoprene from the boundary layer to the upper troposphere and no LNOx is present, OH is reduced due to scavenging by isoprene, which serves to slow the chemistry, resulting in longer lifetimes for species that react with OH. Ozone and PAN production is minimal in this case. In the case where isoprene is convected and LNOx is present, there is a large effect on the expected ensuing chemistry: isoprene exerts a dominant impact on HOx and nitrogen-containing species; the relative contribution from other species to HOx, such as peroxides, is insignificant. The isoprene reacts quickly, resulting in primary and secondary products, including formaldehyde and methyl glyoxal. The model predicts enhanced production of alkyl nitrates (ANs) and peroxyacyl nitrate compounds (PANs). PANs persist because of the cold temperatures of the upper troposphere resulting in a large change in the NOx mixing ratios which, in turn, has a large impact on the HOx chemistry. Ozone production is substantial during the first few hours following the convection to the UT, resulting in a net gain of approximately 10 ppbv compared to the modeled scenario in which LNOx is present but no isoprene is present aloft.
We report on the W and Z/γ∗ differential and total cross sections as well as the W+/W− and (W+ + W−)/(Z/γ∗) cross section ratios measured by the STAR experiment at RHIC in p + p collisions at √s = ...500 GeV and 510 GeV. The cross sections and their ratios are sensitive to quark and antiquark parton distribution functions. In particular, at leading order, the W cross section ratio is sensitive to the d/u ratio. These measurements were taken at high Q2 ∼ M2W, M2Z and can serve as input into global analyses to provide constraints on the sea quark distributions. The results presented here combine three STAR datasets from 2011, 2012, and 2013, accumulating an integrated luminosity of 350 pb−1. We also assess the expected impact that our W+ / W− cross section ratios will have on various quark distributions, and find sensitivity to the u − d and d/u distributions.
The deconfined quark-gluon plasma (QGP) created in relativistic heavy-ion collisions enables the exploration of the fundamental properties of matter under extreme conditions. Noncentral collisions ...can produce strong magnetic fields on the order of 1018 G, which offers a probe into the electrical conductivity of the QGP. In particular, quarks and antiquarks carry opposite charges and receive contrary electromagnetic forces that alter their momenta. This phenomenon can be manifested in the collective motion of final-state particles, specifically in the rapidity-odd directed flow, denoted as v1(y). Here, we present the charge-dependent measurements of dv1/dy near midrapidities for π±, K±, and $p(\bar{p})$ in Au+Au and isobar $(^{96}_{44}Ru+^{96}_{44}Ru$ and $^{96}_{40}Zr+^{96}_{40}Zr)$ collisions at $\sqrt{s_{NN}}=200$ GeV, and in Au+Au collisions at 27 GeV, recorded by the STAR detector at the Relativistic Heavy Ion Collider. The combined dependence of the v1 signal on collision system, particle species, and collision centrality can be qualitatively and semi-quantitatively understood as several effects on constituent quarks. While the results in central events can be explained by the u and d quarks transported from initial-state nuclei, those in peripheral events reveal the impacts of the electromagnetic field on the QGP. Our data put valuable constraints on the electrical conductivity of the QGP in theoretical calculations.
KORUS-AQ was an international cooperative air quality field study in South Korea that measured local and remote sources of air pollution affecting the Korean Peninsula during May–June 2016. Some of ...the largest aerosol mass concentrations were measured during a Chinese haze transport event (24 May). Air quality forecasts using the WRF-Chem model with aerosol optical depth (AOD) data assimilation captured AOD during this pollution episode but overpredicted surface particulate matter concentrations in South Korea, especially PM2.5, often by a factor of 2 or larger. Analysis revealed multiple sources of model deficiency related to the calculation of optical properties from aerosol mass that explain these discrepancies. Using in situ observations of aerosol size and composition as inputs to the optical properties calculations showed that using a low-resolution size bin representation (four bins) underestimates the efficiency with which aerosols scatter and absorb light (mass extinction efficiency). Besides using finer-resolution size bins (8–16 bins), it was also necessary to increase the refractive indices and hygroscopicity of select aerosol species within the range of values reported in the literature to achieve better consistency with measured values of the mass extinction efficiency (6.7 m2 g−1 observed average) and light-scattering enhancement factor (f(RH)) due to aerosol hygroscopic growth (2.2 observed average). Furthermore, an evaluation of the optical properties obtained using modeled aerosol properties revealed the inability of sectional and modal aerosol representations in WRF-Chem to properly reproduce the observed size distribution, with the models displaying a much wider accumulation mode. Other model deficiencies included an underestimate of organic aerosol density (1.0 g cm−3 in the model vs. observed average of 1.5 g cm−3) and an overprediction of the fractional contribution of submicron inorganic aerosols other than sulfate, ammonium, nitrate, chloride, and sodium corresponding to mostly dust (17 %–28 % modeled vs. 12 % estimated from observations). These results illustrate the complexity of achieving an accurate model representation of optical properties and provide potential solutions that are relevant to multiple disciplines and applications such as air quality forecasts, health impact assessments, climate projections, solar power forecasts, and aerosol data assimilation.
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