cssi/SciSciGPT-SciSciNet huggingface dataset:
Surgeon-driven variability in emergency general surgery outcomes: Does it matter who is on call?

Abstract Background Hospital-level variation has been found to influence outcomes in emergency general surgery. However, whether the individual surgeon plays a role in this variation is unknown. Methods We performed an analysis of the Florida State Inpatient Database (2010–2014), which is linked to the American Hospital Association's Annual Survey Database, including patients who emergently underwent 1 or more of 7 procedures (laparotomy, adhesiolysis, small bowel resection, colectomy, repair of a perforated gastric ulcer, appendectomy, or cholecystectomy). We used multilevel random effects modeling to quantify the amount of variation in mortality, complications, and 30-day readmissions attributable to surgeons. Patient clinical and demographic factors, as well as hospital-level factors, were introduced into the model in a forward stepwise fashion, and the percent of the variation attributable to surgeons was derived. Results Our study included 2,149 surgeons across 224 hospitals, with a total of 569,767 emergency general surgery cases. The overall unadjusted mortality rate was 3.8%, and the complication and readmission rates were 12.7% and 27.7%, respectively. Surgeon-level variation had the greatest impact on mortality, explaining 32.77% of the overall variability in mortality risk compared with 0.08% and 2.28% for complications and readmissions, respectively. Peptic ulcer disease operations were most susceptible to surgeon-level variation in mortality and readmissions, whereas appendectomies and cholecystectomies were least susceptible to surgeon-level variation for all outcomes. Conclusions Surgeon-level variation contributes to a significant portion of mortality in EGS. This variation is most pronounced in surgery for peptic ulcer disease, a high-risk, low-frequency surgical condition. Programs to reduce mortality in emergency general surgery should address reducing variability in practice with attention to high-risk, low-frequency procedures.
Primary Lymphedema of the Upper Extremities: Clinical and Lymphoscintigraphic Features in 23 Patients

Abstract Background: Primary idiopathic lymphedema is an uncommon condition that typically affects the lower extremities. Patients have a malformed lymphatic system that causes subcutaneous fluid a...
Navigating the Boundaries of Respectability and Desire: Seagram’s Advertising and the Meanings of Moderation after Repeal

AbstractThis article examines Seagram’s institutional and brand advertising during the 1930s to illuminate how the Canadian distiller often muddied the meanings of moderation and respectability in ...
Robust Sensor Localization against Known Sensor Position Attacks

Many localization techniques for wireless sensor networks have been proposed to estimate sensor positions even when there is malicious location information which distorts the estimate. Some of those solutions efficiently estimate sensor positions using the Minimum Mean Square Estimation methods and the Degree-Of-Consistency (DOC). Although such solutions can filter out most of malicious information, if an attacker knows the position of the target sensor, the attacker can significantly alter its estimated position. In this paper, we introduce two attacks based on the knowledge of target sensor positions. The first attack, called Aligned-Beacon-Position (ABP) attack , exploits beacon nodes that are aligned in a line. The second attack, called inside-attack , disables the DOC filtering algorithm by placing malicious location references inside benign location references. To protect against those two known sensor position attacks, we introduce two defense schemes. First, we propose a novel beacon placement strategy to protect against ABP attacks. Second, we present a filtering technique that can filter out malicious location references introduced by inside-attacks. Finally, we propose a localization algorithm which has enhanced accuracy and efficiency compared with previous algorithms. We assess the impact of those attacks and the performance of our defense schemes by simulation and test-bed experiments.
30 GHz Supercontinuum Generation for Astronomy with Efficient SiN Waveguides

Using silicon nitride waveguides we demonstrate octave spanning spectra at a 30 GHz repetition rate with less than 20 pJ of total pulse energy at 1 μm. This high efficiency supercontinuum enables broadband and robust frequency comb generation for astronomical spectrograph calibration. © 2019 The Author(s)
Microled displays expected in 2020: The last remaining hurdle is mastering mass production - [News]

One of the most striking things about the prototype microLED display that Silicon Valley startup Mojo Vision unveiled in June was its size. At half a millimeter across, it's barely bigger than a single pixel from the microLED TV prototype Samsung showed off in 2018. That both use versions of the same technology is remarkable, and it portends big potential for screens made of superefficient and bright micrometerscale gallium nitride LEDs. Impressive prototypes have proliferated during the past year, and now that companies are turning to the hard work of scaling up their manufacturing processes, displays could appear in some products as soon as late next year.
HIF-independent synthetic lethality between CDK4/6 inhibition and VHL loss across species

Inactivation of the VHL tumor suppressor gene is the signature initiating event in clear cell renal cell carcinoma (ccRCC), the most common form of kidney cancer, and causes the accumulation of hypoxia-inducible factor 2α (HIF-2α). HIF-2α inhibitors are effective in some ccRCC cases, but both de novo and acquired resistance have been observed in the laboratory and in the clinic. Here, we identified synthetic lethality between decreased activity of cyclin-dependent kinases 4 and 6 (CDK4/6) and VHL inactivation in two species (human and Drosophila) and across diverse human ccRCC cell lines in culture and xenografts. Although HIF-2α transcriptionally induced the CDK4/6 partner cyclin D1, HIF-2α was not required for the increased CDK4/6 requirement of VHL-/- ccRCC cells. Accordingly, the antiproliferative effects of CDK4/6 inhibition were synergistic with HIF-2α inhibition in HIF-2α-dependent VHL-/- ccRCC cells and not antagonistic with HIF-2α inhibition in HIF-2α-independent cells. These findings support testing CDK4/6 inhibitors as treatments for ccRCC, alone and in combination with HIF-2α inhibitors.
Building a Boot Camp: Pediatric Residency Preparatory Course Design Workshop and Tool Kit.

Introduction Although many medical schools are adding residency preparatory courses or boot camps to their curricula, there is little published guidance for faculty tasked with designing them. We d...
One Model Does Not Fit All: Bottom-Up Indicators of Residential Water Use Provide Limited Explanation of Urban Water Fluxes

AbstractDemand forecasting for water resources is an essential planning element for cities to provide secure and sustainable water supplies. A common way of determining water demands is to identify...
Liposuction Treatment of a Subacute Morel-Lavallée Lesion: A Case Report.

Introduction A Morel-Lavallee lesion (MLL) is a rare and aesthetically concerning condition caused by a shearing force between subcutaneous fat and underlying fascia. Subsequent seroma formation occurs after the initial trauma of a crush injury, ligamentous sprain, or abdominal liposuction. Misdiagnosed lesions lead to inadequate treatment and are a source of chronic pain. Case report The case of a 33-year-old woman who presented with a large, painful subacute MLL of the left thigh after being run over by a truck 3 weeks prior is reported. Physical examination revealed severe hyperesthesia and fluctuance of the left thigh. After confirmation of the fluid collection by X-ray and computed tomography angiogram, the authors performed liposuction of the cavity and seroma wall to evacuate and treat the lesion. Postoperative care consisted of a temporary drain, thigh compression, and oral antibiotics. Immediate reduction in size was appreciated intraoperatively with no reaccumulation of fluid at postoperative visits on week 1 and week 6. The pathology report confirmed seroma etiology, and all cultures of the fluid returned negative. At the end of her postoperative course, the patient reported a reduction in pain and no recurrence of her symptoms. Conclusions This case of MLL was diagnosed early and successfully treated with liposuction, resulting in an acceptable cosmetic outcome. It is the authors' hope that this case report will lead to earlier diagnosis and proper treatment of MLLs.
H2O-prompted CO2 capture on metal silicates in situ generated from SBA-15

A series of metal silicates, NaMSi10Ox (M = Cu, Mn and Ni), were prepared by in situ doping of metals into mesoporous SBA-15 under a hydrothermal process, displaying a continuous framework of SiO4 structure with a narrow pore size distribution. These metal silicate materials were tested for CO2 adsorption behavior in the absence and presence of water. The results exhibited that the effect of H2O on the CO2 capture capability of metal silicates depends on the types of metal inserted into SBA-15. Compared to the dry condition, H2O addition enhances CO2 uptake dramatically for NaCuSi10Ox by 25%, and slightly for NaNiSi10Ox (∼10%), whereas little effect is shown on NaMnSi10Ox. The metal silicate materials are stable after adsorption of CO2 under wet conditions, which is benefited from their synthesis method, hydrothermal conditions. The improvement of CO2 uptake on metal silicates by H2O is attributed to the competitive and synergistic adsorption mechanism on the basis of IR investigations, where initially adsorbed H2O acts as a promoter for further CO2 capture through a hydration reaction, i.e., formation of bicarbonate and carbonates on the surface of the samples. These observations provide new possibilities for the design and synthesis of porous metal silicate materials for CO2 capture under practical conditions where moisture is present.
A Common Drug With a Dangerous Side Effect: Acute Rhabdomyolysis Caused by the Synergistic Effect of Isotretinoin and Exercise in an Adolescent.

Isotretinoin or 13-cis-retinoic acid, a derivative of vitamin A, is a highly effective therapy for severe and resistant acne. Its usage is restricted worldwide because of its teratogenic potential. The most common side effects are dermatologic, cheilitis, increased skin fragility, and susceptibility to sunburns. Rare side effects include myalgias and arthralgias. It also causes transient laboratory abnormalities such as elevated creatine kinase (CK). Very few cases of isotretinoin-induced severe muscle injury leading to rhabdomyolysis have been reported in the literature. We report a 15-year-old adolescent who developed rhabdomyolysis after a bout of vigorous exercising while on long-term isotretinoin therapy.
“It Felt Like I Had Air Back in My Lungs”: Eleanor’s Journey Back From Burnout:

The purpose of this narrative inquiry was to explore the story of a secondary ensemble teacher who experienced burnout and chose to remain in the profession. Eleanor and I met for three semistructu...
Analysis of Utilization, Cost and Prescription Trends of Mycophenolate Mofetil and Methotrexate Among Medicare Patients

Methotrexate and mycophenolate mofetil (MMF) are antimetabolites used by dermatologists for the treatment of numerous autoinflammatory dermatologic conditions such as atopic dermatitis (AD)[1, 2]. ...
Landscape features associated with the roosting habitat of Indiana bats and northern long-eared bats

Bat conservation in the eastern United States faces threats from white nose syndrome, wind energy, and fragmentation of habitat. To mitigate population declines, the habitat requirements of species of concern must be established. Assessments that predict habitat quality based upon landscape features can aid species management over large areas. Roosts are critical habitat for many bat species including the endangered Indiana bat (Myotis sodalis) and the threatened northern long-eared bat (M. septentrionalis). While much is known about the microhabitat requirements of roosts, translating such knowledge into landscape-level management is difficult. Our goal was to determine the landscape-scale environmental variables necessary to predict roost occupancy for both species. Using MaxLike, a presence-only occupancy modeling approach, with known roost sites, we identified factors associated with roosting habitat. Spatially independent roost locations were particularly limited for northern long-eared bats resulting in differences in study areas and sample sizes between the two species. Occupancy of Indiana bat roosts was greatest in areas with >80 % local forest cover within broader landscapes (1 km) with 1 km from intermittent streams and in areas with poor foraging habitat. Northern long-eared roost occupancy was greatest in areas with >80 % regional but fragmented forest cover with greater forest edge approximately 4 km from the nearest major road. Landscape features associated with roost occupancy differed greatly between species suggesting disparate roosting needs at the landscape scale, which may require independent management of roost habitat for each species.
Solarcatalytic inactivation of Escherichia coli in aqueous solutions using TiO2 as catalyst

Escherichia Coli (E. coli) was used as an index to assess the disinfection of water-borne microorganisms by sunlight irradiation in the presence of a titanium dioxide (TiO2, anatase) photocatalyst. With 23 min. irradiation, more than 99% of the spiked E. Coli was inactivated in water solutions. No significant changes in E. coli were observed in the irradiated control with no TiO2 added, or in the water solution that was not irradiated but contained TiO2. The inactivation of E. coli was attributed to the generation of free hydroxyl radicals during irradiation of TiO2 in the aqueous solution.
Systematic Bias in 2MASS Galaxy Photometry

We report the discovery of a serious bias in galaxy photometry reported in the 2MASS Extended Source Catalog (Jarrett et al. 2000). Due to an undetermined flaw in the 2MASS surface photometry routines, isophotal and total magnitudes calculated by their methods underestimate the luminosity of galaxies from 10% to 40%. This is found to be due to incorrectly determined scalelengths and isophotal radii, which are used to define the aperture sizes for Kron and total fluxes. While 2MASS metric aperture luminosities are correct (and, thus, colors based on those apertures), comparison to other filters (e.g. optical) based on total magnitudes will produce erroneous results. We use our own galaxy photometry package (ARCHANGEL) to determine correct total magnitudes and colors using the same 2MASS images, but with a more refined surface brightness reduction scheme. Our resulting colors, and color-magnitude relation, are more in line with model expectations and previous pointed observations.
Analysis of the complexity of gene regulation by fur in Vibrio cholerae.

Iron concentration influences the expression of a number of genes involved in iron uptake and virulence in bacteria. In Escherichia coli, coordinate regulation of these genes by iron depends on the product of the fur gene, which acts as an iron-responsive, DNA-binding repressor protein. Several genes in Vibrio cholerae are also repressed by iron; and a fur gene, homologous to E. coli fur, has been previously cloned from this organism. The present study was undertaken to define the roles of Fur and iron in regulating gene expression in V. cholerae. V. cholerae strains with a mutation in fur by virtue of suicide plasmid integration into this gene showed derepressed expression of two previously characterized, iron-regulated genes, irgA and viuA, in high concentrations of iron; even in the fur mutants, however, residual two- to threefold regulation by iron persisted. The fur mutant strains constructed by suicide plasmid integration required antibiotic selection to maintain the mutation. To analyze further the effect of Fur and iron on gene regulation in V. cholerae without the need for antibiotic selection, we used in vivo marker exchange to construct a nonrevertible V. cholerae fur mutant. This V. cholerae fur mutant grew significantly less well in Luria-Bertani medium than the wild-type parent but grew slightly better than the wild type under iron-restricted conditions. The V. cholerae fur mutant was unable to utilize a number of carbon sources including glycerol, acetate, succinate, lactate, and fumarate, that supported growth of the wild-type strain on minimal media. We utilized two-dimensional gel electrophoresis of whole-cell protein extracts from the fur mutant and wild-type strains following growth in conditions of either low or high concentrations of iron to identify proteins regulated by iron and/or Fur. Twenty-two proteins were negatively regulated by iron in the wild-type strain but constitutively expressed in the fur mutant, consistent with the model of Fur as an iron-dependent repressor. However, many other proteins were regulated in a different manner by iron and/or Fur. Seventeen proteins were negatively regulated by iron but independent of Fur, suggesting the presence of an additional iron-dependent repressor(s). Six proteins were strongly iron regulated in the fur mutant but hardly expressed at all in the wild-type strain regardless of the iron concentration, suggesting an interaction between Fur and another iron regulatory mechanism. There were 11 proteins that were induced rather than repressed by iron, in four different regulatory classes. Gene regulation in V. cholerae by Fur and iron is much more complex than previously thought and is reminiscent of the Lrp regulon in E.coli.
Focal adhesions and integrin-mediated cell signaling

Publisher Summary Cells secrete, adhere to, and model arrays of extracellular matrix (ECM). The ECM affects many aspects of cell behavior, including their migratory properties, their growth and differentiation. It has been known for some time that addition of the ECM protein, fibronectin, and too many transformed cells in culture will restore a normal phenotype. These effects of fibronectin are due largely to its action of promoting or stabilizing focal adhesions. Under most conditions of cell culture, the surface to which cells adhere is a layer of ECM protein, usually fibronectin or vitronectin derived from serum, adsorbed to the plastic culture dish. Members of the integrin family of ECM receptors are concentrated at focal adhesions and form a transmembrane bridge between the ECM on the outside and the cytoskeleton on the inside. Focal adhesions are also regions of signal transduction between the ECM and the cytoplasm. The prominence of focal adhesions in many cultured cells probably reflects the abnormal conditions in which they are grown, in particular their growth on a rigid planar surface. Prominent components of focal adhesions are integrins, cell surface receptors that mediate adhesion to ECM molecules. This chapter discusses ECM-cytoskeletal interactions, concentrating on integrins and focal adhesions. In addition, the chapter reviews the signaling events triggered by integrin-mediated cell adhesion.
Rapid measurement of perchlorate in polar ice cores down to sub-ng L −1 levels without pre-concentration

An ion chromatography-electrospray ionization-tandem mass spectrometry (IC-ESI-MS/MS) method has been developed for rapid and accurate measurement of perchlorate in polar snow and ice core samples in which perchlorate concentrations are expected to be as low as 0.1 ng L(-1). Separation of perchlorate from major inorganic species in snow is achieved with an ion chromatography system interfaced to an AB SCIEX triple quadrupole mass spectrometer operating in multiple reaction monitoring mode. Under optimized conditions, the limit of detection and lower limit of quantification without pre-concentration have been determined to be 0.1 and 0.3 ng L(-1), respectively, with a linear dynamic range of 0.3-10.0 ng L(-1) in routine measurement. These represent improvements over previously reported methods using similar analytical techniques. The improved method allows fast, accurate, and reproducible perchlorate quantification down to the sub-ng L(-1) level and will facilitate perchlorate measurement in the study of natural perchlorate production with polar ice cores in which perchlorate concentrations are anticipated to vary in the low and sub-ng L(-1) range. Initial measurements of perchlorate in ice core samples from central Greenland show that typical perchlorate concentrations in snow dated prior to the Industrial Revolution are about 0.8 ng L(-1), while perchlorate concentrations are significantly higher in recent (post-1980) snow, suggesting that anthropogenic sources are a significant contributor to perchlorate in the current environment.
pKw Is Almost Never 14.0:: Contribution from the Task Force on the General Chemistry Curriculum

The value of -log([H+][OH-]) is not 14.00 at 25 oC in any circumstance where a student is likely to need it. If calculations are taught that use Kw then the correct value should be used, and should preferably be the Bronsted value aH+[OH-]. Values of pKw under both definitions, have been calculated from published data for various ionic strengths, temperatures, and pressures and tabulated. Calculations of pH are even then reliable only in the first decimal and approximate in the second. Texts deceive their readers when they quote 14.00 and give answers to two decimals. The value of such calculations in first year chemistry is questionable. Some suggestions are offered for teaching qualitative understanding of autoprotolysis. Plots of pKw against temperature or against the ionic strength of the solution pass through a minimum. pKw decreases with increasing pressure.
Generation of Molecular Complexity from Cyclooctatetraene: Preparation of Aminobicyclo[5.1.0]octitols

A series of eight stereoisomeric N-(tetrahydroxy bicyclo-[5.1.0]oct-2S*-yl)phthalimides were prepared in one to four steps from N-(bicyclo[5.1.0]octa-3,5-dien-2-yl)phthalimide (±)-7, which is readily available from cyclooctatetraene (62 % yield). The structural assignments of the stereoisomers were established by (1) H NMR spectral data as well as X-ray crystal structures for certain members. The outcomes of several epoxydiol hydrolyses, particularly ring contraction and enlargement, are of note. The isomeric phthalimides as well as the free amines did not exhibit β-glucosidase inhibitory activity at a concentration of less than 100 μM.
The Elongation and Orientation of Cultured Endothelial Cells in Response to Shear Stress

Vascular endothelial cells appear to be aligned with the flow in the immediate vicinity of the arterial wall and have a shape which is more ellipsoidal in regions of high shear and more polygonal in regions of low shear stress. In order to study quantitatively the nature of this response, bovine aortic endothelial cells grown on Thermanox plastic coverslips were exposed to shear stress levels of 10, 30, and 85 dynes/cm2 for periods up to 24 hr using a parallel plate flow chamber. A computer-based analysis system was used to quantify the degree of cell elongation with respect to the change in cell angle of orientation and with time. The results show that (i) endothelial cells orient with the flow direction under the influence of shear stress, (ii) the time required for cell alignment with flow direction is somewhat longer than that required for cell elongation, (iii) there is a strong correlation between the degree of alignment and endothelial cell shape, and (iv) endothelial cells become more elongated when exposed to higher shear stresses.
Relation Between Infarct Size in ST-Segment Elevation Myocardial Infarction Treated Successfully by Percutaneous Coronary Intervention and Left Ventricular Ejection Fraction Three Months After the Infarct

The goal of this analysis was to determine the relation between myocardial infarct size and left ventricular (LV) ejection fraction (EF) in patients with ST-segment elevation myocardial infarction (STEMI) after primary percutaneous coronary intervention (pPCI) using cardiovascular magnetic resonance imaging (CMR). After STEMI, LVEF and infarct size correlate with prognosis, but the relation between infarct size and LVEF is incompletely known. Consecutive subjects presenting to a single center with STEMI treated with pPCI were enrolled, and cine functional and late gadolinium enhancement CMR was performed 3 months after presentation. From cine images, LVEF was calculated using volumetric summation of disks method. Infarct size was measured as percent LV myocardial volume with late gadolinium enhancement. In the 78 patients enrolled (mean age 54.5 years, range 42 to 82), median LVEF was 56% (interquartile range 49 to 62) and median infarct size was 11% (interquartile range 5 to 18). Of the 53 patients with infarct size 40%, and there was no significant relation between infarct size and LVEF (slope −0.43, R 2 = 0.045, p = 0.13). In patients with infarct size ≥15%, there was a significant negative linear association between infarct size and LVEF (slope −1.21, R 2 = 0.66, p
Receptivity to volunteering in the immediate postretirement period

Higher rates of volunteering might be expected of elders in the period immediately after retirement because they tend to be in relatively good health and have fewer competing obliga tions. Data from the Commonwealth Productive Aging Survey, a telephone survey of a repre sentative national sample of 2,999 people 55 years of age and older, confirmed findings of previous research that retirement is not associated with higher rates of volunteering. However, in the first and second years following termination of employment, nonvolunteers show a heightened receptivity to volunteering; that is, they indicate more willingness to take on volunteer assignments and an ability to do so than do elders who are employed or who have been out of the workforce for longer periods. The findings suggest that volunteer coordinators should focus volunteer recruiting efforts on elders who are about to leave jobs or who have recently left jobs.
Sucrea (Poaceae: Bambusoideae), a new genus from Brazil

Sucrea, a new genus of herbaceous bambusoid grasses is based on the newly described species,S. monophylla. Also belonging to this genus is another new species,S. maculata, and the taxon originally namedOlyra sampaiana. The new genus is contrasted in a key with others of its tribe Olyreae, and a key is given to its three species.
Analytical models for predicting penetration depth during slot die coating onto porous media

A series of analytical models have been developed to predict the penetration depth during slot die coating on porous media. Analytical models for both Newtonian and non-Newtonian fluids were derived based on Lubrication Theory, Darcy's law, and a modified Blake–Kozeny equation. Using these models, the penetration depth can be quickly solved and the effects of material properties and processing conditions on penetration depth can be easily investigated. Experiments of coating Newtonian glycerin and non-Newtonian blackstrap molasses onto Toray series carbon paper were conducted to validate developed models. The overall relative error between the predicted and measured penetration depth was found to be typically lower than 20%, which demonstrates the relative accuracy of developed models. Furthermore, based on a parametric study, it was found that the effect of capillary pressure on penetration depth is less than 10% when the ratio of coating bead pressure and capillary pressure is larger than 10. © 2014 American Institute of Chemical Engineers AIChE J 60: 4241–4252, 2014
Glutamatergic regulation of basal and stimulus-activated dopamine release in the prefrontal cortex

Abstract: The present study was undertaken to determine whether basal and stimulus-activated dopamine release in the prefrontal cortex (PFC) is regulated by glutamatergic afferents to the PFC or the ventral tegmental area (VTA), the primary source of dopamine neurons that innervate the rodent PFC. In awake rats, blockade of NMDA or α-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA) receptors in the VTA, or blockade of AMPA receptors in the PFC, profoundly reduced dopamine release in the PFC, suggesting that the basal output of dopamine neurons projecting to the PFC is under a tonic excitatory control of NMDA and AMPA receptors in the VTA, and AMPA receptors in the PFC. Consistent with previous reports, blockade of cortical NMDA receptors increased dopamine release, suggesting that NMDA receptors in the PFC exert a tonic inhibitory control on dopamine release. Blockade of NMDA or AMPA receptors in the VTA as well as blockade of AMPA receptors in the PFC reduced the dopaminergic response to mild handling, suggesting that activation of glutamate neurotransmission also regulates stimulus-induced increase of dopamine release in the PFC. In the context of brain disorders that may involve cortical dopamine dysfunction, the present findings suggest that abnormal basal or stimulus-activated dopamine neurotransmission in the PFC may be secondary to glutamatergic dysregulation.
Mechanism of OH formation from ozonolysis of isoprene: kinetics and product yields

Abstract The fate of primary ozonides and carbonyl oxides arising from the ozonolysis of isoprene is investigated using a statistical–dynamical master equation and transition state theory. Excited carbonyl oxides are shown to dissociate promptly to produce OH (11%) or isomerize to form dioxirane (32%), while the remaining (57%) are collisionally stabilized. An OH formation yield of 0.25 from prompt (0.11) and thermal (0.14) decomposition of the carbonyl oxide is obtained. The results reveal slow thermal decomposition of the carbonyl oxide to form OH. For formaldehyde, MACR, and MVK, the yields are estimated to be 0.67, 0.21, and 0.12, respectively.
Marine manganese concretions: shape and size related growth models

Abstract Shapes and size distributions of marine manganese concretions affect abundance estimates made from sea floor photographs and act as constraints in modeling their development. Simple cylindrical, spheroidal, or ellipsoidal shapes are found to be inadequate in describing a concretion suite from one box core. Guided by their physical characteristics and the relative concentrations of source materials in the media surrounding developing concretions, their growth is numerically modeled for three special cases. All the models adequately describe the shape of the only known well-measured concretion suite. In all three cases the thickness of a formation layer in which most concretion growth takes place is about 1 to 1.5 cm and lies just below the sediment-water interface. The models can be used to constrain concretion size distributions in light of material demands and limiting sources.
A unification-theoretic method for investigating the k-provability problem

Abstract The k-provability for an axiomatic system A is to determine, given an integer k ⩾ 1 and a formula ϕ in the language of A, whether or not there is a proof of ϕ in A containing at most k lines. In this paper we develop a unification-theoretic method for investigating the k-provability problem for Parikh systems, which are first-order axiomatic systems that contain a finite number of axiom schemata (including individual axioms) and a finite number of rules of inference. We show that the k-provability problem for a Parikh system reduces to a unification problem that is essentially the unification problem for second-order terms. By solving various subproblems of this unification problem (which is itself undecidable), we solve the k- probability problem for a variety of Parikh systems, including several formulations of Peano arithmetic. Our method for investigating the k-provability problem employs algorithms that compute and characterize unifiers. We give some examples of how these algorithms can be used to solve complexity problems other than the k-provability problem.
Career choice and performance on state licensing examinations of "Fifth Pathway" students.

Abstract Between 1975 and 1977, 340 American citizens trained in foreign medical schools (mostly Mexican) completed a year of supervised clinical training (Fifth Pathway) in New York State before b...
Boundary states at reflective moving boundaries

We derive and evaluate boundary states for Maxwell's equations, the linear, and the nonlinear Euler gas-dynamics equations to compute wave reflection from moving boundaries. In this study we use a Discontinuous Galerkin Spectral Element method (DGSEM) with Arbitrary Lagrangian-Eulerian (ALE) mapping for the spatial approximation, but the boundary states can be used with other methods, like finite volume schemes. We present four studies using Maxwell's equations, one for the linear Euler equations, and one more for the nonlinear Euler equations. These are: reflection of light from a plane mirror moving at constant velocity, reflection of light from a moving cylinder, reflection of light from a vibrating mirror, reflection of sound from a plane wall and dipole sound generation by an oscillating cylinder in an inviscid flow. The studies show that the boundary states preserve spectral convergence in the solution and in derived quantities like divergence and vorticity.
Orientation dependence of the distribution coefficient obtained from a spin-1 Ising model

The nonequilibrium distribution coefficient (k neq ) as a function of solid-liquid interface velocity and orientation was investigated for a spin-1 Ising model for binary alloys using Monte Carlo computer simulations. The crystal structure and thermodynamic properties were chosen to correspond to bismuth doped silicon with k eq = 7 x 10 -4 . Values for k neq were obtained for several orientations of the solid/liquid interface, including (111) and (001). For the same growth velocity, k neq was found to be greatest for solid/liquid interfaces parallel to the (111) plane. The orientation dependence is related to variations in the kink site density at the interface. The simulation results are compared with experimental results reported by Aziz et al.
The Potential Harm of Prostate Cancer Health Supplements

Introduction. Products that advertise “prostate health” are readily available at most major supplement and vitamin shops. The SELECT trial, SELenium and vitamin E Cancer prevention Trial, showed that men who were supplemented with vitamin E and selenium faced a higher risk of developing prostate cancer. We opted to look at nationally available products from major retailers that advertised prostate health to determine if they could potentially cause harm by inclusion of selenium and/or vitamin E. Methods. We collected data from national retailers including Vitamin Shoppe, General Nutrition Corporation (GNC), that sell vitamins and supplements. Any product that advertised terms such as “prostate health” or “prostate cancer prevention” or similar were analyzed. In total, 97 products were assessed. The ingredients were analyzed to see if the product contained selenium or vitamin E. The remaining ingredients were also recorded. Results. Of all the products, 17% contained both selenium and vitamin E, 36% had se...
Effect of postweanling pyridoxine deficiency on growth and concentration of the coenzyme pyridoxal-5'-phosphate in heart, kidneys, lungs, and adrenals in rats.

Extract: Dietary pyridoxine deficiency induced in postweanling rats led to severe growth retardation and growth failure, with a sharp increase in the mortality rate after about 8 weeks on the diet. The absolute weights of heart, lungs, kidneys, and adrenals were all lower in the deficient animals than those of the controls. However, when the weights were expressed in terms of percentage of body weight, a 2-fold increase was observed indicative of marked hypertrophy. The depletion of the coenzyme pyridoxal-5′-phosphate from these tissues was extensive (heart 48%, lungs 85%, and kidneys and adrenals 88%). The extent of loss of the coenzyme from the tissues suggests possible functional changes. Speculation: Functional disturbances may be expected as a consequence of the marked hypertrophy and the extensive depletion of the coenzyme pyridoxal-5′-phosphate from the heart, lungs, kidneys, and adrenals in postweanling pyridoxine-deficient rats.
Approximate method for the calculation of nonequilibrium radiative heat transfer

A simplified method for the calculation of radiative heat transfer in hypersonic reentry flows where local thermal nonequilibrium (LTNE) conditions exist is presented. This method has been incorporated into the computer code RADMC (RADiation/Modified Corrections), which utilizes an approximate 'two-state' model of the electronic levels of atoms and molecules in the determination of the populations of the excited states for both LTNE and local thermal equilibrium (LTE) conditions for each of the relevant chemical species. The population data are used to calculate a correction factor to the radiative cross sections in an eight-step nongray radiative heat-transfer model. Results have been obtained for various points along the proposed trajectory of the Aeroassist Flight Experiment and the Fire II trajectory, and compared with results obtained for the same flowfields from the NEQAIR radiative heat-transfer code.
Impact of a disaster on a burn unit.

Abstract The sudden arrival at a burn unit of six critically injured persons requiring immediate and extensive intervention put a severe strain on the unit's resources. Under the pressure of events, the unit's organization and functioning had to change from that of a primarily closed system to a more open one. The authors assess the features of each mode of operation, the emotional reactions of the staff, and the effects of the provision of consultation-liaison services to the unit and the patients. The liaison psychiatrist became closely involved in conveying the wishes of patients and families in the difficult matter of how far unavoidably painful intensive treatment should continue for persons with minimal prospects for survival.
Prevalence and predictors of hookah use in US Air Force military recruits.

Abstract Introduction Hookah use has gained recent popularity among U.S. youth. The current study describes the characteristics and correlates associated with hookah use in late adolescent and young adult US Air Force (USAF) recruits. Methods Data were obtained from a cross-sectional questionnaire of USAF personnel in Technical Training School at Joint Base San Antonio (N = 10,997). Response rate was 78%. Logistic regression was used to analyze the associations between hookah use, demographic variables, other tobacco and nicotine containing product (TNCP) use, and the social environment. Results The prevalence of ever hookah use was 28%; at least monthly hookah use was 10%. Increased hookah use was positively associated with Hispanic ethnicity (OR [odds ratio] 1.52; 95% CI: 1.25, 1.85), cigarette smoking (OR 4.05; CI: 3.41, 4.82) and smokeless tobacco use (OR 1.35; 95% CI: 1.07, 1.71). Hookah use was negatively associated with age (OR 0.84; 95% 0.71 to 1.00), living as married (OR 0.54; 95% CI: 0.40–0.72), African American (OR 0.53; 95% CI: 0.40, 0.69) and ≥ 4-year degree (OR 0.54; 95% CI: 0.35, 0.82). Hookah use was highest among recruits who “many or almost all” of their friends smoked cigarettes (OR 2.43; 95% CI: 1.80, 3.30) and for those who reported willingness to try a tobacco product that claims to be safer than cigarettes (OR 3.16; 95% CI: 2.64, 3.77). Conclusions Hookah use among military recruits is similar to the civilian population. A willingness to try TNCPs claiming to be safer than cigarettes may influence hookah use. Public health campaigns disseminating accurate information about hookah health risks may be needed to reduce hookah use among youth.
Are the ratios of bill crossing morphs in crossbills the result of frequency-dependent selection?

The direction the lower mandible curves in crossbills (Loxia) is an example of a discrete polymorphism. The lower mandible crosses with equal frequency to the left and to the right in several crossbill populations. I hypothesize that the 1:1 ratio results from negative frequency-dependent selection favouring the rarer morph. A crossbill always orients toward closed conifer cones so that its lower mandible is directed towards the cone axis. Thus, only part of the cone can be reached easily when crossbills have few perch sites and the cone cannot be removed from the branch or otherwise turned round. Since crossbills may visit cones which have previously been foraged on by other individuals, an equal frequency of left-to-right mandible crossings may minimize overlap in the use of cones and enhance foraging efficiency. Experimental data support this hypothesis. Moreover, the variation in the ratio of mandible crossing directions among crossbill populations is consistent with this hypothesis.
Evidence for two-band superconductivity from break-junction tunneling on MgB2.

Superconductor-insulator-superconductor tunnel junctions have been fabricated on ${\mathrm{MgB}}_{2}$ that display Josephson and quasiparticle currents. These junctions exhibit a gap magnitude, $\ensuremath{\Delta}\ensuremath{\sim}2.5\mathrm{meV}$, that is considerably smaller than the BCS value, but which clearly and reproducibly closes near the bulk ${T}_{c}$. In conjunction with fits of the conductance spectra, these results are interpreted as direct evidence of two-band superconductivity.
Operative Correction of Total Left Anomalous Pulmonary Venous Return

The evaluation, surgical repair, and follow-up are described in an asymptomatic 27-year-old man with unilateral total anomalous pulmonary venous return from the left lung through an innominate vein and a patent foramen ovale. The anomalous vein was divided and anastomosed directly to the left atrium using a vascular technique that produced an orifice larger than the vein diameter. Radionuclide scanning accurately identified the anomaly before operation and allows periodic noninvasive reevaluation after operation. Correction is recommended in all patients with unilateral anomalous pulmonary venous return because disease in the one normal lung could be fatal.
Semi-automated competitive protein binding analysis of serum thyroxine on reusable sephadex columns and its advantages over radioimmunoassay

Abstract Competitive protein-binding analysis of serum thyroxine on small, reusable. Sephadex columns has been further studied and improved. The improved, semi-automated procedure results in reduced working time and costs. It has also been established that triiodothyronine crossreacts only 1/6 to 1/9 as well as thyroxine, and can be ignored because it represents only about. 1/80 of the total serum iodothyronine content. The economic and methodological advantages of the improved method over radioammunoassay and other displacement assays are discussed.
Activation energies for addition of O(3P) to simple olefins

Description of relative rate measurements for the addition of O(3P) to C2H4, C2F4, C3H6, and C4H8-1 in liquid argon at 87.5 K. The data strongly indicate that the activation energies for the addition of O(3P) to the double bonds of propylene and butene-1 are identical, probably to within 0.1 kcal/mole. It is very doubtful that differences in pre-exponential factors or other factors such as solvent effects, could invalidate this conclusion. A similar argument holds for the C2H4 and C2F4 reactions. Furthermore, the experiments suggest that the activation energy for addition of O(3P) to the double bond of butene-1 is about 0.1 kcal/mole.
Monitoring Bering Sea ice change using reconstructed NSCAT imagery

Scatterometers are active microwave instruments designed to measure ocean wind speed and direction. Recently they have been tested for the mapping of sea ice. In preparation for the launch of QuikSCAT, the goal of this research was to develop an ice delineation algorithm for the Bering Sea using reconstructed NASA scatterometer data. The algorithm was designed to utilize simple backscatter, image texture, and vertical/horizontal polarization ratios to track the advance of the Bearing Sea ice edge during late winter of 1997. The results of the image processing were compared to the published National Ice Center maps for the same period. There was good agreement between the two products. The greatest challenge in developing the algorithm was detecting the sea ice in areas of very low concentration.
Interventions to Reduce Missed Telephone Appointments at an Employee Assistance Program

ABSTRACT This study investigated two interventions delivered during an intake procedure to 60 female and 15 male employee clients seeking telephone counseling in the employee assistance program (EAP) of a large diversified financial corporation. Clients receiving the “direct request” intervention were asked to keep their appointments out of courtesy to their counselors; clients receiving the “brief solution-focused” intervention were asked to reflect on their current coping strategies and informed that their counselors would be interested in hearing about these strategies. The effect of these two interventions on client no-show rates and counselor satisfaction ratings, as reported by 5 female and 2 male counselors, was examined. No significant differences were found between treatment and control groups. In addition, the waiting time before client appointments was found to have no significant effects on no-show rates. These results conflict to some extent with earlier research findings, and may reflect dif...
Developmental and situational differences in coping among children and adolescents with diabetes

Abstract Children and adolescents with diabetes indicated how they coped with three diabetes-related situations (diabetes-related social, diet, fingerprick) and a general peer-argument situation. Children utilized approach-coping strategies (i.e., problem solving, seeking social support) more frequently than adolescents. Both the approach- and avoidance-coping strategies (i.e., internalizing, externalizing, distancing) were highly and positively correlated accross situations. Across all four situations, approach-coping strategies were used more frequently than avoidance-coping strategies. Approach-coping strategies were used less frequently for dealing with finger-pricks than the other situations. Avoidance-coping strategies were used more frequently for a general peer argument than the diabetes-related situations. In hierarchical regressions, after controlling for age, coping strategies accounted for a significant portion of the variance in predicting some global adjustment indices (grade point average, depression) and situation-specific, self-rated coping effectiveness. Higher levels of approach coping and lower levels of avoidance coping were generally related to more positive outcomes.