Efficacy of a hybrid technique of simultaneous videolaryngoscopy with flexible bronchoscopy in children with difficult direct laryngoscopy in the Pediatric Difficult Intubation Registry.

Children with difficult tracheal intubation are at increased risk of severe complications, including hypoxaemia and cardiac arrest. Increasing experience with the simultaneous use of videolaryngoscopy and flexible bronchoscopy (hybrid) in adults led us to hypothesise that this hybrid technique could be used safely and effectively in children under general anaesthesia. We reviewed observational data from the international Pediatric Difficult Intubation Registry from 2017 to 2021 to assess the safety and efficacy of hybrid tracheal intubation approaches in paediatric patients. In total, 140 patients who underwent 180 attempts at tracheal intubation with the hybrid technique were propensity score-matched 4:1 with 560 patients who underwent 800 attempts with a flexible bronchoscope. In the hybrid group, first attempt success was 70% (98/140) compared with 63% (352/560) in the flexible bronchoscope group (odds ratio (95%CI) 1.4 (0.9-2.1), p = 0.1). Eventual success rates in the matched groups were 90% (126/140) for hybrid vs. 89% (499/560) for flexible bronchoscope (1.1 (0.6-2.1), p = 0.8). Complication rates were similar in both groups (15% (28 complications in 182 attempts) hybrid; 13% (102 complications in 800 attempts) flexible bronchoscope, p = 0.3). The hybrid technique was more likely than flexible bronchoscopy to be used as a rescue technique following the failure of another technique (39% (55/140) vs. 25% (138/560), 2.1 (1.4-3.2) p < 0.001). While technically challenging, the hybrid technique has success rates similar to other advanced airway techniques, few complications and may be considered an alternative technique when developing an airway plan for paediatric patients whose tracheas are difficult to intubate under general anaesthesia.

Heterogeneous mass distribution of the rubble-pile asteroid (101955) Bennu.

The gravity field of a small body provides insight into its internal mass distribution. We used two approaches to measure the gravity field of the rubble-pile asteroid (101955) Bennu: (i) tracking and modeling the spacecraft in orbit about the asteroid and (ii) tracking and modeling pebble-sized particles naturally ejected from Bennu's surface into sustained orbits. These approaches yield statistically consistent results up to degree and order 3, with the particle-based field being statistically significant up to degree and order 9. Comparisons with a constant-density shape model show that Bennu has a heterogeneous mass distribution. These deviations can be modeled with lower densities at Bennu's equatorial bulge and center. The lower-density equator is consistent with recent migration and redistribution of material. The lower-density center is consistent with a past period of rapid rotation, either from a previous Yarkovsky-O'Keefe-Radzievskii-Paddack cycle or arising during Bennu's accretion following the disruption of its parent body.

Observations, Meteorites, and Models: A Preflight Assessment of the Composition and Formation of (16) Psyche.

Some years ago, the consensus was that asteroid (16) Psyche was almost entirely metal. New data on density, radar properties, and spectral signatures indicate that the asteroid is something perhaps even more enigmatic: a mixed metal and silicate world. Here we combine observations of Psyche with data from meteorites and models for planetesimal formation to produce the best current hypotheses for Psyche's properties and provenance. Psyche's bulk density appears to be between 3,400 and 4,100 kg m-3. Psyche is thus predicted to have between ~30 and ~60 vol% metal, with the remainder likely low-iron silicate rock and not more than ~20% porosity. Though their density is similar, mesosiderites are an unlikely analog to bulk Psyche because mesosiderites have far more iron-rich silicates than Psyche appears to have. CB chondrites match both Psyche's density and spectral properties, as can some pallasites, although typical pallasitic olivine contains too much iron to be consistent with the reflectance spectra. Final answers, as well as resolution of contradictions in the data set of Psyche physical properties, for example, the thermal inertia measurements, may not be resolved until the NASA Psyche mission arrives in orbit at the asteroid. Despite the range of compositions and formation processes for Psyche allowed by the current data, the science payload of the Psyche mission (magnetometers, multispectral imagers, neutron spectrometer, and a gamma-ray spectrometer) will produce data sets that distinguish among the models.

Cratering on Ceres: Implications for its crust and evolution.

Thermochemical models have predicted that Ceres, is to some extent, differentiated and should have an icy crust with few or no impact craters. We present observations by the Dawn spacecraft that reveal a heavily cratered surface, a heterogeneous crater distribution, and an apparent absence of large craters. The morphology of some impact craters is consistent with ice in the subsurface, which might have favored relaxation, yet large unrelaxed craters are also present. Numerous craters exhibit polygonal shapes, terraces, flowlike features, slumping, smooth deposits, and bright spots. Crater morphology and simple-to-complex crater transition diameters indicate that the crust of Ceres is neither purely icy nor rocky. By dating a smooth region associated with the Kerwan crater, we determined absolute model ages (AMAs) of 550 million and 720 million years, depending on the applied chronology model.

Dawn arrives at Ceres: Exploration of a small, volatile-rich world.

On 6 March 2015, Dawn arrived at Ceres to find a dark, desiccated surface punctuated by small, bright areas. Parts of Ceres' surface are heavily cratered, but the largest expected craters are absent. Ceres appears gravitationally relaxed at only the longest wavelengths, implying a mechanically strong lithosphere with a weaker deep interior. Ceres' dry exterior displays hydroxylated silicates, including ammoniated clays of endogenous origin. The possibility of abundant volatiles at depth is supported by geomorphologic features such as flat crater floors with pits, lobate flows of materials, and a singular mountain that appears to be an extrusive cryovolcanic dome. On one occasion, Ceres temporarily interacted with the solar wind, producing a bow shock accelerating electrons to energies of tens of kilovolts.

A partially differentiated interior for (1) Ceres deduced from its gravity field and shape.

Remote observations of the asteroid (1) Ceres from ground- and space-based telescopes have provided its approximate density and shape, leading to a range of models for the interior of Ceres, from homogeneous to fully differentiated. A previously missing parameter that can place a strong constraint on the interior of Ceres is its moment of inertia, which requires the measurement of its gravitational variation together with either precession rate or a validated assumption of hydrostatic equilibrium. However, Earth-based remote observations cannot measure gravity variations and the magnitude of the precession rate is too small to be detected. Here we report gravity and shape measurements of Ceres obtained from the Dawn spacecraft, showing that it is in hydrostatic equilibrium with its inferred normalized mean moment of inertia of 0.37. These data show that Ceres is a partially differentiated body, with a rocky core overlaid by a volatile-rich shell, as predicted in some studies. Furthermore, we show that the gravity signal is strongly suppressed compared to that predicted by the topographic variation. This indicates that Ceres is isostatically compensated, such that topographic highs are supported by displacement of a denser interior. In contrast to the asteroid (4) Vesta, this strong compensation points to the presence of a lower-viscosity layer at depth, probably reflecting a thermal rather than compositional gradient. To further investigate the interior structure, we assume a two-layer model for the interior of Ceres with a core density of 2,460-2,900 kilograms per cubic metre (that is, composed of CI and CM chondrites), which yields an outer-shell thickness of 70-190 kilometres. The density of this outer shell is 1,680-1,950 kilograms per cubic metre, indicating a mixture of volatiles and denser materials such as silicates and salts. Although the gravity and shape data confirm that the interior of Ceres evolved thermally, its partially differentiated interior indicates an evolution more complex than has been envisioned for mid-sized (less than 1,000 kilometres across) ice-rich rocky bodies.

Uncertainty in biogenic isoprene emissions and its impacts on tropospheric chemistry in East Asia.

In this study, the accuracy of biogenic isoprene emission fluxes over East Asia during two summer months (July and August) was examined by comparing two tropospheric HCHO columns (ΩHCHO) obtained from the SCIAMACHY sensor and the Community Multi-scale Air Quality (CMAQ v4.7.1) model simulations, using three available biogenic isoprene emission inventories over East Asia: i) GEIA, ii) MEGAN and iii) MOHYCAN. From this comparative analysis, the tropospheric HCHO columns from the CMAQ model simulations, using the MEGAN and MOHYCAN emission inventories (Ω(CMAQ, MEGAN) and Ω(CMAQ, MOHYCAN)), were found to agree well with the tropospheric HCHO columns from the SCIAMACHY observations (Ω(SCIA)). Secondly, the propagation of such uncertainties in the biogenic isoprene emission fluxes to the levels of atmospheric oxidants (e.g., OH and HO2) and other atmospheric gaseous/particulate species over East Asia during the two summer months was also investigated. As the biogenic isoprene emission fluxes decreased from the GEIA to the MEGAN emission inventories, the levels of OH radicals increased by factors of 1.39 and 1.75 over Central East China (CEC) and South China, respectively. Such increases in the OH radical mixing ratios subsequently influence the partitioning of HO(y) species. For example, the HO2/OH ratios from the CMAQ model simulations with GEIA isoprene emissions were 2.7 times larger than those from the CMAQ model simulations based on MEGAN isoprene emissions. The large HO2/OH ratios from the CMAQ model simulations with the GEIA biogenic emission were possibly due to the overestimation of GEIA biogenic isoprene emissions over East Asia. It was also shown that such large changes in HO(x) radicals created large differences on other tropospheric compounds (e.g., NO(y) chemistry) over East Asia during the summer months.

Dawn at Vesta: testing the protoplanetary paradigm.

The Dawn spacecraft targeted 4 Vesta, believed to be a remnant intact protoplanet from the earliest epoch of solar system formation, based on analyses of howardite-eucrite-diogenite (HED) meteorites that indicate a differentiated parent body. Dawn observations reveal a giant basin at Vesta's south pole, whose excavation was sufficient to produce Vesta-family asteroids (Vestoids) and HED meteorites. The spatially resolved mineralogy of the surface reflects the composition of the HED meteorites, confirming the formation of Vesta's crust by melting of a chondritic parent body. Vesta's mass, volume, and gravitational field are consistent with a core having an average radius of 107 to 113 kilometers, indicating sufficient internal melting to segregate iron. Dawn's results confirm predictions that Vesta differentiated and support its identification as the parent body of the HEDs.

Prediction of wheat chemical and physical characteristics and nutritive value by near-infrared reflectance spectroscopy.

1. The aims of this study were to investigate the potential of near infrared reflectance spectroscopy (NIRS) to predict the chemical and physical characteristics of wheat and also to predict the nutritive value of wheat for broiler chickens. 2. A total of 164 wheat samples, collected from a wide range of different sources (England, Northern Ireland and Canada), varieties and years, were used in this study. 3. Chemical and physical parameters measured included specific weight, thousand grain weight, in vitro viscosity, gross energy, nitrogen, neutral detergent fibre (NDF), starch, total and soluble non-starch polysaccharides (NSP), lysine, threonine, amylose, hardness, rate of starch digestion and protein profiles. 4. A total of 94 wheat samples were selected for inclusion in three bird trials and included at 650 g/kg in a typical UK starter/grower diet. Birds were housed in individual wire metabolism cages from 7 to 28 d and offered water and food ad libitum. Dry matter intake (DMI), live weight gain (LWG) and gain:feed ratio were measured weekly. A balance collection was carried out from d 14 to 21 for determination of apparent metabolisable energy (AME), ME:gain and dry matter retention. At 28 d the birds were humanely killed, the contents of the jejunum removed for determination of in vivo viscosity and the contents of the ileum removed for determination of ileal dry matter, starch and protein digestibility. 5. The wheat samples were scanned as whole and milled wheat, both dried and undried and NIRS calibrations, first excluding and then including the Canadian wheat samples, were developed. 6. NIRS calibrations for milled wheat samples may be useful for determining specific weight (R(cv)(2) = 0.75, for milled wheat dried), nitrogen (R(cv)(2) = 0.983 for milled and dried) and rate of starch digestion (R(cv)(2) = 0.791 for milled, dried and undried). 7. NIRS calibrations for whole wheat samples (undried) may be useful for determining wheat nutritive value, with good predictions for live weight gain (R(cv)(2) = 0.817) and feed conversion efficiency (R(cv)(2) = 0.825). 8. Inclusion of the Canadian wheat samples in the NIRS analysis provided additional robust calibrations for gross energy (R(cv)(2) = 0.86, dried and milled) and starch content (R(cv)(2) = 0.79, undried and milled). 9. This study shows that NIR is a useful tool in the accurate and rapid determination of wheat chemical parameters and nutritive value and could be extremely beneficial to both the poultry and wheat industry. 10. Further extension of the dataset would be recommended to further validate these findings.

Displaced intra-articular calcaneal fracture treated surgically with limited posterior incision.

The incidence of calcaneal fracture has been slowly increasing; however, the ideal treatment for displaced intra-articular fracture is not available yet, even though the fracture brings frequent complication and disability. Between April 1991 and March 1998, we treated 103 displaced intra-articular calcaneal fractures of 92 patients surgically with limited posterior incision, modified Gallie approach. There were thirty-seven tongue-type fractures, fifteen tongue-type fractures with moderate comminution, nineteen joint-depression fractures, twenty-nine joint-depression fractures with moderate comminution, and three extensively comminuted fractures. The fracture fragments were fixed mainly with partly threaded small cancellous screws or Steinmann pins without any bone graft. Ankle and subtalar motion was permitted immediately if fixation were stable enough. Otherwise, a short period of cast immobilization was utilized. With a mean follow-up of 28 months (range, 12 to 66 months), eighty six percent of feet had no pain or only occasional pain not requiring medication. Using American Orthopedic Foot and Ankle Society hindfoot score system for assessment, ninety percent of feet rated as good to excellent. We used "Circle draw test" for evaluation of subtalar motion during follow-up visitation and found eight-seven percent of feet showed good to excellent correlation with the functional recovery. We recommend a limited posterior incision for reduction and internal fixation of displaced intra-articular calcaneal fractures. For displaced intra-articular fractures with three or four large fragments without further comminution and without a displaced fracture of the calcaneal cuboid joint, this method is particularly useful. We also recommend a Circle draw test for evaluation of subtalar joint motion as well as an indicator of functional recovery after displaced calcaneal fractures.

Evaluation of a saliva alcohol test stick as a therapeutic adjunct in an alcoholism treatment program.

This study was designed to evaluate the clinical usefulness of a saliva alcohol dipstick by comparing dipstick saliva alcohol concentrations to simultaneous blood and urine alcohol concentrations. The sample consisted of 211 saliva tests and blood alcohol concentrations and 189 urine alcohol concentrations. The dipsticks had a specificity of 0.965, a sensitivity of 0.895, a positive predictive value of 0.850, a negative predictive value of 0.977 and a Pearson's product moment correlation coefficient of 0.609 for blood alcohol concentrations and salivary alcohol concentrations, suggesting that the saliva dipstick is useful as a qualitative test in certain settings but is less useful than previously reported as a semiquantitative test.

Incorporation of different types of n-3 fatty acids into tissue lipids of poultry.

The objective of the present study was to compare the incorporation of different types of n-3 polyunsaturated fatty acids into thigh muscle lipids of poultry. Nine groups of broiler chicks were fed diets supplemented with three levels (1.0, 2.5, and 5.0%) of either corn, linseed, or menhaden oil. Birds supplemented with linseed oil, rich in linolenic acid (C18:3n-3), had significantly higher levels of n-3 fatty acids and higher n-3:n-6 ratios than those supplemented with the same level of menhaden oil, primarily due to an accumulation of C18:3n-3. Levels of eicosapentaenoic acid (C20:5n-3) were increased (P less than .05), compared with the controls fed the same level of corn oil, in the groups fed the two higher levels of linseed oil, and in all the groups fed menhaden oil. Linolenic acid is less susceptible to auto-oxidation, and is less likely to impart an off-flavor to the muscle. Thus, if it is desirable to increase the n-3:n-6 ratio in poultry, seed meals or oils with a high content of C18:3n-3 could be used in poultry feeds.

Perinuclear microtubules in postnatal rat heart.

Cytoplasmic microtubules can be divided into two subpopulations: 1) those adjacent to the nucleus (perinuclear), and 2) those distributed between the myofilament bundles (nonperinuclear). Previous observations (Cartwright and Goldstein, '83) indicate total cytoplasmic microtubule numeric density increases to a maximum at 5-9 days and decreases to the steady value of the adult muscle. We have examined the numeric density (mean numbers of microtubule profiles per micron2 cross-sectional area) of the perinuclear subpopulation and compared it to the numeric density of the total cytoplasmic microtubule population in postnatally developing rat papillary muscle ages 1, 3, 5, 9, 21, and 42 days, and adult. The perinuclear region was defined as the area around the nucleus which extends to the 0.273 micron from the nuclear envelope. The density of perinuclear microtubules did not change with postnatal development. Our study suggests that perinuclear microtubules are a separate and relatively stable subpopulation of the total population of cytoplasmic microtubules and may serve a function different from that of the more variable nonperinuclear microtubules.