A patient’s hemoglobin (Hb) A1c level, regardless of diabetic status, is a measure of glycemic control. Studies have found it is an independent predictor of short-term death in patients undergoing ...coronary artery bypass grafting (CABG). In this study, we used preoperative HbA1c to assess whether levels are associated with short-term and long-term survival after CABG.
From a regional registry of consecutive cases, we identified 6,415 patients undergoing on-pump isolated CABG from 2008 to 2015 with documented preoperative HbA1c level. We defined four HbA1c groups: less than 5.7% (n = 1,713), 5.7% to 6.4% (n = 2,505), 6.5% to 8.0% (n = 1,377), and more than 8% (n = 820). Relationship to in-hospital outcomes and long-term survival was assessed. Outcome rates and hazard ratios were adjusted for patient and disease risk factors using multivariable logistic regression and Cox models.
The study included 3,740 patients (58%) not diagnosed as having diabetes and 2,674 with diabetes. Prediabetes (HbA1c 5.7% to 6.4%) was documented in 52% (n = 1,933) of nondiabetic patients. Higher HbA1c values were associated with younger age, female sex, greater body mass index, more comorbid diseases, lower ejection fraction, more 3-vessel coronary disease, and recent myocardial infarction (p < 0.05 trend for all). After adjustment for patient risk, greater HbA1c values were not associated with higher rates of in-hospital death or morbidity. Long-term survival was significantly worse as HbA1c increased. Risk of death increased by 13% for every unit increase in HbA1c (adjusted hazard ratio, 1.13; 95% confidence interval, 1.07 to 1.19; p < 0.001).
Preadmission glycemic control, as assessed by HbA1c, is predictive of long-term survival, with higher levels associated with poorer prognosis. Whether this risk can be modified by better glycemic control postoperatively remains to be determined.
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Larvae of the tortoise beetles Charidotella bicolor and Deloyala guttata carry shields formed from exuviae and feces over their bodies that are though to provide protection from natural enemies. We ...investigated the effectiveness of shields as a defense against three groups of invertebrate predators (mandibulate, piercing/sucking and chelicerate taxa) common in tortoise beetle habitats. Choice experiments, functional response studies, measurements of predator body size and mouthpart length, and a literature review indicated that predators with long piercing/sucking mouthparts (i.e., Heteroptera) were the most effective predators of tortoise beetles. For example, relatively large heteropterans with long, piercing/sucking mouthparts (e.g., Nabis americoferus and Podisus maculiventris) were not deterred by shields whereas small predators with short beaks (e.g., Geocoris punctipes) were. Likewise, coccinellid predators with short mandibles were deterred by the shield, while a carabid predator with long mandibles (Lebia fuscata) was effective at killing tortoise beetle larvae. No clear patterns of the effectiveness of shields against chelicerate predators were evident. Choice experiments also indicated that small tortoise beetle larvae were more susceptible to predator attack than were larger instars. Additionally, the effectiveness of the shields against different predators was quite similar between the two tortoise beetles. Field experiments indicated that predators are an important source of mortality for tortoise beetle larvae in natural settings, and high larval mortality is associated with elevated densities of predators with piercing/sucking mouthparts, such as heteropterans. Thus, shields provide some but not universal protection against the variety of predators present in tortoise beetle communities.
The facile heterodehydrocoupling of a range of primary or secondary amines and even ammonia with pinacolborane (HBPin) was accomplished using {Ar
Sn(μ-OMe)}
(1, Ar
= C
H
-2,6-(C
H
-2,4,6-Me
)
) as ...pre-catalysts for a catalytically active tin(ii) hydride. The more sterically hindered pre-catalyst 2, {Ar
Sn(μ-OMe)}
(Ar
= C
H
-2,6-(C
H
-2,6-iPr
)
) facilitated the dehydrocoupling only of primary amines with HBPin, and at an increased rate relative to the less crowded {Ar
Sn(μ-OMe)}
. Also presented is {Ar
Sn(μ-NEt
)}
(3), which can be converted into the structurally characterizable {Ar
Sn(μ-NEt
)(μ-H)SnAr
} (4) via the addition of pinacol borane. This, alongside stoichiometric studies, give insight into the mechanism of the catalysis.
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•This article presents definitive structural characterization of the gold cluster, Au11(PPh3)7(SCN)3.•Although this cluster was the first molecular gold cluster to be ...crystallographically identified, the data available at the time only showed the positions of the gold atoms and the phosphorus and sulfur atoms but without distinguishing between them.•We now have been able to crystallize this cluster in three different forms that differ significantly in the position of the thiocyanate ligands, which have a bent Au-S-CN structure.•The presence of ten large ligands on the cluster surface makes for a crowded environment but the thiocyanate ligands are able to reorient during crystal formation.
The crystallization of two solvates of Au11(PPh3)7(SCN)3, 2Au11(PPh3)7(SCN)3·2C6H6·0.5EtOH (1) and Au11(PPh3)7(SCN)3·3EtOH (2), with (1) containing two independent molecules of the cluster, allows the positions of all of the ligands to finally be identified. Despite the bent nature of the thiocyanate ligands, they occupy similar sites to the ones that contain halogen ligands in Au11(PPh3)7Cl3, Au11(PPh3)7I3, and related molecules. However, the relative orientations of these thiocyanate ligands differ in the three cluster sites.
We report a detection of the baryon acousticoscillation (BAO) feature in the flux-correlation function of the Lyα forest of high-redshift quasars with a statistical significance of five standard ...deviations. The study uses 137 562 quasars in the redshift range 2.1 ≤ z ≤ 3.5 from the data release 11 (DR11) of the Baryon Oscillation Spectroscopic Survey (BOSS) of SDSS-III. This sample contains three times the number of quasars used in previous studies. The measured position of the BAO peak determines the angular distance, DA(z = 2.34) and expansion rate, H(z = 2.34), both on a scale set by the sound horizon at the drag epoch, rd. We find DA/rd = 11.28 ± 0.65(1σ)+2.8-1.2 (2σ) and DH/rd = 9.18 ± 0.28(1σ) ± 0.6(2σ) where DH = c/H. The optimal combination, ~DH0.7DA0.3/rd is determined with a precision of ~2%. For the value rd = 147.4 Mpc, consistent with the cosmic microwave background power spectrum measured by Planck, we find DA(z = 2.34) = 1662 ± 96(1σ) Mpc and H(z = 2.34) = 222 ± 7(1σ) km s-1 Mpc-1. Tests with mock catalogs and variations of our analysis procedure have revealed no systematic uncertainties comparable to our statistical errors. Our results agree with the previously reported BAO measurement at the same redshift using the quasar-Lyα forest cross-correlation. The autocorrelation and cross-correlation approaches are complementary because of the quite different impact of redshift-space distortion on the two measurements. The combined constraints from the two correlation functions imply values of DA/rd that are 7% lower and 7% higher for DH/rd than the predictions of a flat ΛCDM cosmological model with the best-fit Planck parameters. With our estimated statistical errors, the significance of this discrepancy is ≈2.5σ.
Abstract
We present cosmological results from the final galaxy clustering data set of the Baryon Oscillation Spectroscopic Survey, part of the Sloan Digital Sky Survey III. Our combined galaxy sample ...comprises 1.2 million massive galaxies over an effective area of 9329 deg2 and volume of 18.7 Gpc3, divided into three partially overlapping redshift slices centred at effective redshifts 0.38, 0.51 and 0.61. We measure the angular diameter distance DM
and Hubble parameter H from the baryon acoustic oscillation (BAO) method, in combination with a cosmic microwave background prior on the sound horizon scale, after applying reconstruction to reduce non-linear effects on the BAO feature. Using the anisotropic clustering of the pre-reconstruction density field, we measure the product DMH from the Alcock–Paczynski (AP) effect and the growth of structure, quantified by fσ8(z), from redshift-space distortions (RSD). We combine individual measurements presented in seven companion papers into a set of consensus values and likelihoods, obtaining constraints that are tighter and more robust than those from any one method; in particular, the AP measurement from sub-BAO scales sharpens constraints from post-reconstruction BAOs by breaking degeneracy between DM
and H. Combined with Planck 2016 cosmic microwave background measurements, our distance scale measurements simultaneously imply curvature Ω
K
= 0.0003 ± 0.0026 and a dark energy equation-of-state parameter w = −1.01 ± 0.06, in strong affirmation of the spatially flat cold dark matter (CDM) model with a cosmological constant (ΛCDM). Our RSD measurements of fσ8, at 6 per cent precision, are similarly consistent with this model. When combined with supernova Ia data, we find H
0 = 67.3 ± 1.0 km s−1 Mpc−1 even for our most general dark energy model, in tension with some direct measurements. Adding extra relativistic species as a degree of freedom loosens the constraint only slightly, to H
0 = 67.8 ± 1.2 km s−1 Mpc−1. Assuming flat ΛCDM, we find Ωm = 0.310 ± 0.005 and H
0 = 67.6 ± 0.5 km s−1 Mpc−1, and we find a 95 per cent upper limit of 0.16 eV c
−2 on the neutrino mass sum.
Arterial conduits are preferred to venous conduits for coronary artery bypass grafting because of longer patency. A single internal mammary artery (SIMA) is used routinely. Bilateral internal mammary ...arteries (BIMA) are used less frequently. We sought to determine whether BIMA were superior to SIMA.
From our regional registry of consecutive open heart operations, we identified 47,984 patients who underwent isolated coronary artery bypass grafting from 1992 to 2014. Of the 1,482 BIMA patients, 1,297 were propensity matched to a cohort of SIMA patients. Short-term outcomes were compared using standard statistical techniques. Long-term survival was compared using Kaplan-Meier estimators and compared using a log-rank test.
BIMA patients were younger and had fewer comorbid conditions than SIMA patients. After propensity weighting, BIMA and SIMA patients were well matched. There was no difference in in-hospital outcomes for BIMA versus SIMA patients for mortality (1.2% n = 15 vs 0.8% n = 10, p = 0.315), stroke (0.7% n = 9 vs 0.7% n = 9), p = 1.000), bleeding (2.2% n = 28 vs 2.8% n = 36, p = 0.311), or mediastinitis (0.8% n = 10 vs 0.9% n = 12, p = 0.667). The median follow-up was 12 years. Survival was better for BIMA than SIMA (adjusted hazard ratio, 0.79; 95% confidence interval, 0.69 to 0.91; p < 0.001). Survival curves began to separate after 5 years. At 15 years, the absolute difference in survival was 8.4%.
In a large regional experience, BIMA is associated with no upfront risk of adverse events and improved long-term survival compared with SIMA. Our results indicate that BIMA conduits should be considered more frequently during coronary artery bypass grafting due to their demonstrated survival advantage.
While several nonchromatographic methods are available for the isolation and purification of endohedral fullerenes of the type M3N@Ih-C80, little work has been done that would allow other members of ...the M3N@C2n family to be isolated with minimal chromatography. Here, we report that Gd3N@D2(35)-C88 can be isolated from the multitude of endohedral and empty cage fullerenes present in carbon soot obtained by electric-arc synthesis using Gd2O3-doped graphite rods. The procedure developed utilizes successive precipitation with the Lewis acids CaCl2 and ZnCl2 followed by treatment with amino-functionalized silica gel. The structure of the product was identified by single-crystal X-ray diffraction.
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