cssi/SciSciGPT-SciSciNet huggingface dataset:
Hypothesis test for causal explanations in human pathology: evaluation of pulmonary edema in 181 autopsied patients with leukemia☆

Abstract Symbolic logic, as used in the formal theory of scientific explanation proposed by Hempel and Oppenheim, has been suggested as the basis for automated medical diagnosis. In human autopsy pathology the determination of cause-and-effect relationships is a major area subject to logical analysis. We propose a modification of the Hempel-Oppenheim schema in which the logical relationships must only be satisfied “much” of the time, as determined by binomial significance tests. The analysis employs “certainty levels” logic with a more limited consistency requirement than classical logic. The analysis is applied to a series of 181 autopsied patients with leukemia in an attempt to determine a possible role of chemotherapeutic agents in the etiology of pulmonary edema. Among 51 patients who had received cytosine arabinoside (Ara-C) within 30 days of death, there was significantly more unexplained moderate or massive pulmonary edema than among patients with no or remote therapy (p
Comparative investigation on non-IPR C68 and IPR C78 fullerenes encaging Sc3N molecules.

A computational study on the experimentally detected Sc 3 N@C 6 8 cluster is reported, involving quantum chemical analysis at the B3LYP/6-31G* level. Extensive computations were carried out on the pure C 6 8 cage which does not conform with the isolated pentagon rule (IPR). The two maximally stable C 6 8 isomers were selected as initial Sc 3 N@C 6 8 cage structures. Full geometry optimization leads to a confirmation of an earlier assessment of the Sc 3 N@C 6 8 equilibrium geometry (Nature 2000, 408, 427), namely an eclipsed arrangement of Sc 3 N in the C 6 8 6140 frame, where each Sc atom interacts with one pentagon pair. From a variety of theoretical procedures, a D 3 h structure is proposed for the free Sc 3 N molecule. Encapsulated into the C 6 8 enclosure, this unit is strongly stabilized with respect to rotation within the cage. The complexation energy of Sc 3 N@C 6 8 cage is found to be in the order of that determined for Sc 3 N@C 8 0 and exceeding the complexation energy of Sc 3 N@C 7 8 . The cage-core interaction is investigated in terms of electron transfer from the encapsulated trimetallic cluster to the fullerene as well as hybridization between these two subsystems. The stabilization mechanism of Sc 3 N@C 6 8 is seen to be analogous to that operative in Sc 3 N@C 7 8 . For both cages, C 6 8 and C 7 8 , inclusion of Sc 3 N induces aromaticity of the cluster as a whole.
Optimization technique for long-term generation expansion planning using the maximum principle and the Gaussian distribution function

Abstract This paper presents a new approach to optimal long-range generation planning. A completely new analytical approach to the production costing model and reliability measure is developed under the assumption of a Gaussian probability distribution for the random load fluctuations and plant outages. The long-range generation investment problem is formulated as an optimal control problem to determine optimally the annual investment in new generation capacity. The Hamiltonian minimization is performed by using a version of the gradient projection method.
Hyperventilation before resistance exercise: cerebral hemodynamics and orthostasis.

Hyperventilation performed by athletes during preparation for resistance exercise might contribute to reports of postexercise orthostatic instability. Purpose: To test the hypothesis that post-resistance exercise orthostatic instability is associated with exaggerated reductions of cerebral blood-flow velocity after hyperventilation. Methods: We recorded the ECG, end-tidal CO2, beat-by-beat finger arterial pressure, and cerebral blood-flow velocity in 10 healthy subjects. Subjects performed 10 repetitions of recumbent leg press using resistance equivalent to 80% of their six-repetition maximum during three separate trials (randomized): 1) no prior hyperventilation (NOHV); 2) after hyperventilation to an end-tidal CO2 of 3% (HV3%); and 3) after hyperventilation to an end-tidal CO2 of 2% (HV2%). After exercise, subjects stood upright for 10 s and rated symptoms of lightheadedness on a scale of 1 (none) to 5 (faint). Results: Mean cerebral blood-flow velocity (CBFVMEAN) increased by 12% during exercise after NOHV and decreased by 14 and 25% during exercise after HV3% and HV2% (all P < 0.0001). During standing, mean arterial pressure (MAP) decreased by 96 mm Hg and CBFVMEAN decreased by 41 cm·s-1 (pooled across conditions; all P < 0.0001). Absolute reductions of CBFVMEAN during standing were greater after HV2% compared with both NOHV and HV3% (P = 0.003). Ratings of perceived lightheadedness during standing increased with prior hyperventilation (P = 0.02) and correlated to the magnitude of reductions in MAP (r = 0.51; P = 0.003) and CBFVMEAN (r = 0.37; P = 0.04). Conclusions: Hyperventilation before lower-body resistance exercise exacerbates CBFVMEAN reductions during standing. Increased symptoms of orthostatic instability are associated with the magnitude of reductions in both MAP and CBFVMEAN.
A numerical method for predicting the stress distribution and soil deformation under a tractor wheel

Abstract The Finite Element Method was employed for predicting the stress distribution and soil deformation under a stationary and moving tractor wheel. The stationary wheel problem was analysed by assuming that the soil-wheel contact area was cicular and the load applied by the wheel was distributing uniformly. Non-linear behaviour of soil was included in the analysis and the technique used for non-linar analysis is discussed in detail. The predicted stress distribution was compared with that obtained from elastic theory and found to be in good agreement. The moving wheel problem was solved for two different values of wheel slip, considering it as a plane strain problem and assuming the soil to be linearly elastic. The results showed wheel slip to have very little effect on the zone affected by the tractor load.
Height, Weight, Wartime Stress, and Older Age Mortality: Evidence from the Union Army Records

Abstract Important determinants of older age mortality among a group of white Union Army veterans were (1) both past and current nutritional status, as proxied by adult height and body mass index, and (2) wartime stress, as proxied by wounds received, discharges due to illness, and prisoner of war status. The body mass and height optima are the same as found for contemporary industrialized populations, suggesting that height and weight standards derived from current industrialized nations can be applied to the developing countries and past populations. Changes in body mass index since the turn of the century accounted for roughly 20% of the decline in mortality from 1900 to 1986.
A Design Method for Thermosyphon Solar Domestic Hot Water Systems

A modification to the f-Chart method has been developed to predict monthly and annual performance of thermosyphon solar domestic hot water systems. Stratification in the storage tank is accounted for through use of a modified collector loss coefficient. The varying flow rate throughout the day and year in a thermosyphon system is accounted for through use of a fixed monthly ''equivalent average'' flow rate. The ''equivalent average'' flow rate is that which balances the thermosyphon buoyancy driving force with the frictional losses in the flow circuit on a monthly average basis. Comparison between the annual solar fraction predicted by the modified design method and TRNSYS simulations for a wide range of thermosyphon systems shows an RMS error of 2.6 percent.
Seven things to consider when measuring religious identity

Measuring religious identity is complex. The author offers seven suggestions for those who wish to describe and understand religious identity using survey data: (1) Definitions and measures of religious identity shape knowledge about religious groups;(2) Variation in question wording leads to variation in responses;(3) Comparing results across surveys provides valuable perspective;(4) Incentives shape how respondents report their religious identity;(5) Religious identity may be liminal;(6) Salient identity categories are often unmeasured; and(7) Religious identity and religious practice may not seem congruent.This essay includes many examples to illustrate these measurement suggestions.
Vertically graded anisotropy in Co/Pd multilayers

Depth grading of magnetic anisotropy in perpendicular magnetic media has been predicted to reduce the field required to write data without sacrificing thermal stability. To study this prediction, we have produced Co/Pd multilayers with depth-dependent Co layer thickness. Polarized neutron reflectometry shows that the thickness grading results in a corresponding magnetic anisotropy gradient. Magnetometry reveals that the anisotropy gradient promotes domain nucleation upon magnetization reversal---a clear experimental demonstration of the effectiveness of graded anisotropy for reducing write field.
Using a bird community index to evaluate national parks in the urbanized national capital region

Land managers and conservationists face two challenges in protecting land: first balancing human needs against conservation goals, and second demonstrating protected areas are meeting those goals. In this paper, we address the second challenge, using the National Parks of the highly urbanized mid-Atlantic as an example. We detail a comprehensive measure of overall ecosystem integrity, the bird community index, and demonstrate how it relates to the underlying habitat structure. We use community bird data collected from point counts to generate a single, comprehensive metric that we show is significantly correlated to habitat features, making it an effective tool for evaluating ecological integrity. Next, using the metric, we compare bird communities within and outside of protected status, and find that National Parks maintain higher integrity bird communities. This result provides evidence that even smaller parks in highly urbanized areas afford a conservation benefit. More broadly, we find that this rapid and cost effective assessment tool, the bird community index, shows great promise in helping land managers evaluate protected areas.
Phosphate transport and signaling

The discovery of phosphate (Pi) transporter genes has provided a basis for the molecular study of the complex pattern of Pi transport in plants. Over the past two years, a significant amount of information has been generated on the molecular regulation of phosphate transport in plants. Recent developments in plant genomics will soon allow the complete dissection of the signal transduction pathway(s) associated with plant responses to Pi limitation in the rhizosphere.
Nutritional issues for adolescents

This chapter provides background on the nutritional health of adolescents, focusing on a public health or population-level approach. We detail some specific nutritional issues and related health outcomes that are particularly relevant to adolescents, including overweight and obesity, type 2 diabetes, eating-related disorders and bone health as it relates to calcium intake. We discuss implications of the trends in adolescent dietary habits for practitioners and propose a research agenda for better understanding and positively influencing future adolescent nutritional health.
Dielectric constant of Y-stabilized zirconia, the polarizability of zirconia and the oxide additivity rule

Abstract The dielectric constant of the Y-stabilized zirconia, Zr .894 Y .095 Hf .011 O 1.95 , was determined to be 28.6 ± 0.2 at 1 MHz using a two-terminal method and empirically determined edge corrections. The dielectric polarizability of ZrO 2 derived from dielectric constants of several Zr compounds is 7.30 A 3 . The agreement between measured dielectric polarizabilities as determined from the Clausius-Mosotti equation and those calculated from the sum of oxide polarizabilities according to α D (mineral) = Σ α D (oxide) for zircon and three Y-stabilized zirconia samples is ∼0.5%.
The Airline Lifesaver: A 17-year analysis of a technique to prompt the delivery of a safety message

This paper analyzes the findings from a simple, large-scale technique for reminding people to use their seat belts. The Airline Lifesaver (AL) is a small card delivered by a passenger to a flight attendant on a commercial airline in order to prompt the delivery of an important safety message. The AL requests the following safety-belt reminder be added to the regular announcements given at the end of the flight: "Now that you have worn a seat belt for the safest part of your trip, the flight crew would like to remind you to buckle-up during your ground transportation." The AL was handed to 1,258 flight attendants over a 17-year period and compliance with the request for the safety message was systematically tracked. Slightly more than one-third of the AL cards included an incentive for making the announcement. Without the incentive, compliance to give the buckle-up reminder was 35.5% of 798 flights. With the incentive, compliance was significantly higher at 53.3%. The validity of the AL intervention is discussed with regard to its relevance to cognitive dissonance and consistency theory, and broad-based applicability as a component of community-wide efforts to facilitate a safety-focused culture. The 17-year study also demonstrated a practical and cost-effective application of a behavior-based incentive program. The AL card was found to stimulate positive conversation about safety belt use, which can help defray the negative feeling states that often accompany an enforcement approach for increasing vehicle safety belt use.
Pharmacodynamic Interactions of Antibiotics Alone and in Combination

Clinical trials show that the area under the inhibitory curve (AUIC) is predictive of antibacterial killing rates in patients with nosocomial pneumonia and is useful for predicting clinical or microbiological outcomes and making dosage adjustments with beta-lactams, quinolones, aminoglycosides, and vancomycin. The AUIC values of two antibiotics are additive, and since antibiotics are often given in combination, determining the AUIC for antibiotic combinations could potentially predict the microbiological outcomes for patients given these combinations. To further address this question, mathematical modeling was used to study in vitro pharmacokinetic and pharmacodynamic interactions of the antimicrobials piperacillin and ciprofloxacin. These agents were also studied in vivo in healthy volunteers. Blood samples were obtained for analysis of serum drug concentrations, and serum inhibitory titers were determined against eight common bacterial pathogens, chosen to reflect the range of MIC values to ciprofloxacin and piperacillin. Additive AUIC relationships predictive of bacterial killing rates were typical in patients given these antibiotics in combination.
The history of prosthetic dentistry

Abstract Progress has been made toward rehabilitating dental cripples. We pride ourselves on our dexterity and successful manipulation of our restorations. However, do we really evidence a skill more remarkable than the Etruscans, Phoenicians, Egyptians, and others when they, thousands of years ago, demonstrated with their crude instruments their wonderful attainments in dentistry? As J. H. Bass 4 wrote: "Millions and millions have perished without contributing to the progress of science; they have no history. Thousands have promoted at least the foundation of future knowledge; history records their names, for they labored. They summed up the past and discovered new and great truths, the intellectual products of many bygone factors of knowledge; they led humanity onward, and thus formed the landmarks of its history".
The concept of trigonal additivity

Abstract The trigonal additivity procedure proposed by the authors has proved to be the most precise and accurate procedure for estimating thermodynamic properties of highly branched alkanes and alkane derivatives. Herein it is demonstrated that Brown's linear combination of bond orbitals (LCBO) equation for alkanes is not only the basis for the trigonal additivity procedure but also serves as a basis for less comprehensive group additivity correlations proposed by investigators during the last three decades.
The enhanced work hardening rates of the constituent TiAl and Ti3Al phases in a lamellar microstructure

Abstract The minimum creep rate of a two-phase TiAl/Ti 3 Al alloy with a lamellar microstructure is significantly lower than the minimum creep rates of single-phase TiAl and Ti 3 Al alloys tested in compression at the same temperature and applied stress. It has been proposed previously that the arrangement and increased density of geometrically necessary dislocations in a plastically inhomogeneous lamellar microstructure enhance the work hardening rate and decrease the minimum creep rate compared with the constituent single-phase alloys. In support of this proposition, a strong correlation has been found between the increase in dislocation densities and decrease in minimum creep rates of the TiAl and Ti 3 Al phases within the lamellar microstructure compared with the constituent single-phase alloys.
SU‐E‐I‐125: Uniform Sampling of Projections during Pulsed Electron Paramagnetic Resonance Imaging Data Acquisition

Purpose: To devise a generalized, object‐independent method for uniform acquisition of projections from 3D pulsed electron paramagnetic resonanceimaging (EPRI) experiments so that intermediate images approximating the final image may be reconstructed from an incomplete set of projections.Methods: Projection directions for 3D pulsed EPRI experiments can be represented as points on a hemisphere. A new technique is developed to divide the hemisphere into sectors of equal area and sample the projection points such that the standard deviation of the number of these points per sector is minimized. These sectors are defined by number of divisions in azimuthal and polar angles. Images of a cylindrical phantom were obtained using the current polar‐azimuthal raster scheme as well as this new uniform sampling scheme with different hemisphere divisions for comparison of rapidity of convergence to the final image. The mean square difference between intermediate images and the final image was the metric compared.Results: The uniform‐sampling method produces intermediate images that converge to the true final image more rapidly. An imagereconstructed from half projection data is 44.6% closer to the final image than an imagereconstructed from half projection data using the polar‐ azimuthal raster method. Conclusions: A novel method is developed to uniformly sample projection data for 3D pulsed EPRI that is independent of the object and produces intermediate images converging to the fully sampled image more rapidly than those from a polar‐azimuthal raster sampling scheme. This method can be implemented to allow the user to view the image being created while acquiring projections so that problems with the scan become evident earlier without the need to wait for the entire scan to finish. This new scheme also gives better temporal resolution with the addition of minor artifacts by under sampling projections and requiring less imaging time. Acknowledgement of support: R01 CA98575; P41 EB002034
SU-GG-T-462: Intra-Fractional Motion of Bony Targets in the Spine and Pelvis During Extra-Cranial SRS Treatment

Purpose: to quantify intra‐fractional motion of bony targets with respect to the immobilization cradle during extra‐cranial SRStreatments.Method and Materials: Pre and post treatment cone beam scans were acquired of 64 patients undergoing either single fraction or hypo‐fractionated therapy to tumors in the torso. The median dose delivered in a treatment session was 24 Gy. In the cone beam scans, both the target and the immobilization cradle are visible. Target shifts were determined by computing the difference in the target to target 3D registration, and the cradle to cradle 3D registration. Cradle to cradle registration was done manually. The registration target was either the involved vertebra, or the vertebra at the level of the actual target. Target registration was done automatically using a region of interest encompassing the target vertebra and extending midway into the adjacent vertebrae. Patients were monitored throughout treatment using a stereoscopic infra‐red tracking system.Results: The mean and standard deviation of the shift in target position in the left‐right, posterior‐anterior, and superior‐inferior directions were 0.0±1.4, 0.0±1.0, and 0.2±1.2 mm respectively. The rotations about the corresponding axes, determined from a separate 6D fit, were 0.0±0.7, 0.0±0.5, and 0.0±0.7 degrees, respectively. The length of time between the pre and post treatment scans was 48±15 minutes (mean±std.dev). No correlation was seen between the magnitude of the target shift and the length of time between scans, or between the magnitude of shift and the vertebral level. No indications of radiation induced myelopathy have been seen. Outliers (shifts > 3mm in at least one direction) were seen in 8 patients. Conclusion: Although this form of immobilization works well for most patients, the existence of outliers indicates the importance of infra‐red surveillance.
Receptor subtype and density determine the coupling repertoire of the 5-ht2 receptor subfamily

The 5-Hydroxytryptamine (5-HT)2C receptor (originally known as the 5-HT1C receptor) is a member of the 5-HT2 subfamily of G protein coupled receptors, which is known to couple to phospholipase C. Within the 5-HT2 subfamily, only the 5-HT2C receptor also coupled to inhibition of forskolin-stimulated cAMP production when expressed at high density (12 pmol/mg membrane protein) in stably transformed AV12 cells. The 5-HT2C receptor coupled with high efficacy to both phospholipase C as measured by IP3 (inositol 1,4,5-trisphosphate) production and to inhibition of forskolin-stimulated cAMP production (EC50 = 2.98 nM +/- 0.9 and IC50 = 47.99 nM +/- 10.25 respectively). The 5-HT2A and 5-HT2B receptors, while coupling to phospholipase C with high affinity (EC50s of 19.24 nM +/- 6.44 and 1.24 nM +/- 0.136 respectively), did not decrease adenylyl cyclase activity. The 5-HT2C receptor actions in both systems showed the expected pharmacology for the 5-HT2C receptor, e.g., mesulergine antagonized the effects of 5-HT and spiperone did not. Preincubation of cells with PTX showed that the G protein coupling of the 5-HT2C receptor to phospholipase C is PTX insensitive, while the G protein coupling to inhibition of adenylyl cyclase is PTX sensitive, even to concentrations as low as 20 ng/ml of PTX. PTX pretreatment of the 5-HT2C bearing cells also unmasked a small stimulatory effect on adenylyl cyclase. When expressed at low density the 5-HT2C receptor potentiated forskolin-stimulated cAMP production by 2 fold while still maintaining its ability to enhance PI hydrolysis. A more modest potentiation of cAMP production was noted with low density expression of the 5-HT2B receptor. Thus the ability of the 5-HT2C receptor to interact with several effectors through at least two different G proteins is, in part, receptor subtype specific but also influenced by receptor density.
An SE-tree-based prime implicant generation algorithm

Prime implicants/implicates (PIs) have been shown to be a useful tool in several problem domains. In model-based diagnosis (MBD), de Kleer et al. (Proc. AAAI-90) have used PIs to characterize diagnoses. We present a PI generation algorithm which, although based on thegeneral SE-tree-based search framework, is effectively an improvement of aparticular PI generation algorithm proposed by Slagle et al. (IEEE Trans. Comput. 19(4) (1970)). The improvement is achieved via adecomposition tactic which is boosted by the SE-tree-based framework. The new algorithm is also more flexible in a number of ways. We present empirical results comparing the new algorithm to the old one, as well as to current PI generation algorithms.
Markov-Type inequalities and the Degree of Convex Spline Interpolation

It has been shown by Passow and Roulier [S] and by McAllister and Roulier [6] that it is impossible to interpolate convex data by a smooth, convex, piecewise polynomial with lixed knots and bounded degree, inde- pendent of the data and knots. Indeed, a lower bound for this degree is given in [6] and [8] which shows that a suitable choice of the j.-coordinates of the data points can make the degree as large as desired. In this paper. we show that the lower bound mentioned above is best possible. This is accomplished by observing that the classical Markov inequality cannot be improved by restricting consideration to convex in- creasing polynomials.
CRT-174 Transradial vs Transulnar Access for Coronary Angiography - A Meta-analysis

Transradial access for coronary angiography is widely used because of the low risk of complications and faster ambulation times for patients. Ulnar artery can also be easily accessed for coronary angiography. We compared the safety and efficacy of this approach in this meta-analysis. PubMed, EBSCO
Surgical residents’ operative experience: Impact of the 80-hour work week

Abstract Introduction: Since July 1, 2003 an 80-hour weekly limit to surgical residents' work hours has been enforced by the ACGME. It is not known whether this limit will reduce residents' operative experience. Methods: Quantity and quality of all residents' operative experience rotating on a busy surgical service was examined. Cases in which residents participated were categorized as either minor, major open, minimally invasive, or lines/endoscopy. Residents' average number of cases per day were compared by level of training (senior on the service, PGY-3 or above, and juniors, PGY-1 and 2) in each subcategory, comparing residents on service before (n = 47, twelve consecutive months) and after (n = 33, eight months) implementation of the 80-hour limit. Analysis utilized a two-tailed Student's t test. Results: No significant change in overall number of cases was found for either senior (before, 1.6 +/− 0.4 versus after, 2.0 +/− 0.7 cases/day, P=ns) or junior residents (0.7 +/− 0.2 cases/day both before and after). Juniors' experience did not change in any case category, and neither did seniors', except in lines/endoscopy (before, 0.4 +/− 0.2 versus after, 0.9 +/− 0.4 cases/day, P Conclusions: Within the first eight months since implementation of the work-hour limit, residents' surgical experience has remained essentially equivalent, both in number of cases and in case variety. Further long-term studies are needed, however, to fully assess the impact of the new regulations on surgical education.
Carbon protection and fire risk reduction: toward a full accounting of forest carbon offsets

Management of forests for carbon uptake is an important tool in the effort to slow the increase in atmospheric CO2 and global warming. However, some current policies governing forest carbon credits actually promote avoidable CO2 release and punish actions that would increase long-term carbon storage. In fire-prone forests, management that reduces the risk of catastrophic carbon release resulting from stand-replacing wild-fire is considered to be a CO2 source, according to current accounting practices, even though such management may actually increase long-term carbon storage. Examining four of the largest wildfires in the US in 2002, we found that, for forest land that experienced catastrophic stand-replacing fire, prior thinning would have reduced CO2 release from live tree biomass by as much as 98%. Altering carbon accounting practices for forests that have historically experienced frequent, low-severity fire could provide an incentive for forest managers to reduce the risk of catastrophic fire and asso...
Monolayer film behavior of polymers and their mixtures

The monomolecular film behavior of polyvinyl acetate (PVAc), polyethyl acrylate (PEA) and mixtures of these ranging in concentration ratio of PEA to PVAc from 0.008 to 11.301 has been studied using a Langmuir-type filmbalance over an aqueous 0.01N HCl substrate. Hysteresis was observed in the compression–expansion cycle for PVAc. A discussion of polymer–polymer interaction in a mixed monomolecular film at an interface is presented. The extent of this interaction for films comprising PVAc and PEA has been determined in terms of deviations of the film area from the ideal behavior. The data on the film areas of PVAc and PEA are discussed in terms of the molecular orientation of these polymers on the surface. A simple equilibrium thermodynamic treatment is applied to the data on mixed monolayer films. The implications resulting from this study are discussed.
Angioedema in the emergency department: the impact of angiotensin-converting enzyme inhibitors.

Angiotensin-converting enzyme (ACE) inhibitors have been reported to cause angioedema. The purpose of this study was to establish what proportion of patients who present to the emergency department (ED) with angioedema were concomitantly taking any of the ACE inhibitors and to show how this group differed in presentation and response to treatment from the larger population of patients with non-ACE inhibitor-related angioedema. An 8-year retrospective chart review of all patients with the diagnosis of angioedema observed from January 1, 1984 to December 31, 1991 was undertaken in the ED of an urban teaching hospital. Forty-nine patients ranging from 12 to 88 years of age with symptoms and physical examination that was consistent with the diagnosis of angioedema were entered onto the study. Twelve cases of ACE inhibitor-related angioedema were identified, all occurring in the last 4 years of the review, and when compared with the non-ACE inhibitor-related group were older (mean age, 63.3 vs 43.0 years), had less of an allergic history (0% vs 49%; P = .013), but demonstrated the same severity of symptoms and response to medical therapy. No case required an artificial or surgical airway. ACE inhibitor related angioedema is becoming a common type of angioedema observed in this ED. These patients are older and free of other allergic disease and respond well to traditional therapy.
More evidence that light isomerises the chromophore of purple membrane protein

LIGHT absorption by the purple membrane protein (bacterio-rhodopsin) of Halobacterium halobium leads to pumping of protons across the cell membrane1; the resulting proton gradient can in turn be used to make ATP2,3. As in photosynthesis, the energy for this proton pumping must be ultimately derived from the energy of the absorbed photon which is converted into chemical free energy in the formation of the primary photochemical product, bathobacteriorhodopsin or K (refs 4 and 5) (see Fig. 1). On warming, K decays to the photocycle intermediate L and then to M4, which, after warming to higher temperatures, returns to purple membrane protein (PM). The chromophore of the native pigment is all-trans retinal attached to the protein by way of a protonated Schiff base6,7. The question arises : What is the action of light on the chromophore which results in K formation? In earlier papers5,16, we have provided a partial answer to the nature of K by marshalling strong evidence that, as in visual pigments8, the primary effect of light is to isomerise the chromophore. Pettei et al.9 have recently shown using a chromophore extraction method that by the time of M formation, at least part and perhaps all of the chromophores have been isomerised to the 13-cis conformation. Resonance Raman studies of the chromophore of the pigment and its M intermediate also suggest that the chromophore is isomerised from the all-trans to the 13-cis conformation by the time of M formation7. We show here that when M or L is irradiated at −196 °C, their primary photoproducts—M′ or L′—can reform the original pigment when warmed to −90 °C. This property of these new photoproducts can most readily be explained if light has photoisomerised the chromophore of the intermediates back to the conformation originally present in the pigment. Thus, by the L and M intermediates in the photocycle, light has altered the geometry of the chromophore from the all-trans to another geometrical conformation.
BK virus DNA: complete nucleotide sequence of a human tumor virus

The complete DNA sequence of the human papovavirus BK is presented. From the 4963 base-pair sequence of BK virus (MM strain), the amino acid sequence of at least five proteins can be deduced: a T antigen and a t antigen, which share amino terminal peptides; proteins VP2 and VP3, which share 232 amino acids; and protein VP1, whose coding sequence overlaps those for VP2 and VP3 by 113 nucleotides but is read in a different frame. The gene loci and the arrangement of genes are strikingly similar in BK virus and simian virus 40 (SV40). The sequence of the deduced proteins in BK virus shares 73 percent amino acid homology with those in SV40, whereas the DNA sequence of the two viruses shares 70 percent homology, suggesting close evolutionary relationship. However, the repeated DNA sequences in the noncoding regions of these viruses are different.
Metabolic flux analysis of hepatocyte function in hormone- and amino acid-supplemented plasma

Understanding the metabolic and regulatory pathways of hepatocytes is important for biotechnological applications involving liver cells. Previous attempts to culture hepatocytes in plasma yielded poor functional results. Recently we reported that hormone (insulin and hydrocortisone) and amino acid supplementation reduces intracellular lipid accumulation and restores liver-specific function in hepatocytes exposed to heparinized human plasma. In the current study, we performed metabolic flux analysis (MFA) using a simplified metabolic network model of cultured hepatocytes to quantitively estimate the changes in lipid metabolism and relevant intracellular pathways in response to hormone and amino acid supplementation. The model accounts for the majority of central carbon and nitrogen metabolism, and assumes pseudo-steady-state with no metabolic futile cycles. We found that beta-oxidation and tricarboxylic acid (TCA) cycle fluxes were upregulated by both hormone and amino acid supplementation, thus enhancing the rate of lipid oxidation. Concomitantly, hormone and amino acid supplementation increased gluconeogenic fluxes. This, together with an increased rate of glucose clearance, caused an increase in predicted glycogen synthesis. Urea synthesis was primarily derived from ammonia and aspartate generated through transamination reactions, while exogenous ammonia removal accounted for only 3-6% of the urea nitrogen. Amino acid supplementation increased the endogenous synthesis of oxaloacetate, and in turn that of aspartate, a necessary substrate for the urea cycle. These findings from MFA provide cues as to which genes/pathways relevant to fatty acid oxidation, urea production, and gluconeogenesis may be upregulated by plasma supplementation, and are consistent with current knowledge of hepatic amino acid metabolism, which provides further credence to this approach for evaluating the metabolic state of hepatocytes under various environmental conditions.
Mixed Standard Scale Response Inconsistencies as Reliability Indices

The mixed standard scale is a rating format which allows researchers to count illogical (i.e., internally inconsistent) response patterns. These counts have been interpreted as an index of rater reliability, based on the notion that illogical response patterns reflect carelessness in responding. This study investigated the meaning of these counts, using 943 accountants as raters. It was found that the counts of illogical response patterns were not related to reliability as measured by Cronbach's alpha, and alternative interpretations for such indices are suggested.
Electron Beam Computed Tomography and Coronary Artery Disease: Scanning for Coronary Artery Calcification

Objective To review the association of coronary artery calcification with coronary atherosclerosis and its potential clinical application as detected on electron beam computed tomography (EBCT). Design A literature review of coronary artery calcification, coronary artery disease, and EBCT is presented, and clinical applications of EBCT are discussed. Results Recent studies have confirmed that arterial calcification is an active process intimately associated with atherosclerotic plaque evolution. Clinical investigations with use of EBCT have shown that a scan "negative" for coronary calcification is common in patients with normal or near-normal findings on coronary angiography, whereas patients with severe obstructive disease most commonly have "positive" scansxgreater amounts of coronary artery calcium are associated with more severe luminal disease. Coronary artery calcium as evaluated on EBCT follows patterns that reflect the development of coronary atheromatous disease as a function of age and gender. Although histologic studies have confirmed that not all atherosclerotic segments have detectable calcification, the area of coronary artery calcification quantified on EBCT has a direct, positive relationship with the histopathologic coronary plaque area. Conclusion The long-held notion of "degenerative" calcification of the coronary arteries with aging is incorrect. Although the incidence of coronary artery calcification increases with patient age, this relationship simply parallels the increased incidence of coronary atherosclerosis with advancing age. Data suggest that EBCT is a highly sensitive and specific test for coronary atherosclerosis and provide a basis for clinical applications when EBCT is viewed as a noninvasive method to estimate human coronary atherosclerotic involvement and "plaque burxden."
Peering through the mist: systematic review of what the chemistry of contaminants in electronic cigarettes tells us about health risks

Electronic cigarettes (e-cigarettes) are generally recognized as a safer alternative to combusted tobacco products, but there are conflicting claims about the degree to which these products warrant concern for the health of the vapers (e-cigarette users). This paper reviews available data on chemistry of aerosols and liquids of electronic cigarettes and compares modeled exposure of vapers with occupational safety standards. Both peer-reviewed and “grey” literature were accessed and more than 9,000 observations of highly variable quality were extracted. Comparisons to the most universally recognized workplace exposure standards, Threshold Limit Values (TLVs), were conducted under “worst case” assumptions about both chemical content of aerosol and liquids as well as behavior of vapers. There was no evidence of potential for exposures of e-cigarette users to contaminants that are associated with risk to health at a level that would warrant attention if it were an involuntary workplace exposures. The vast majority of predicted exposures are < <1% of TLV. Predicted exposures to acrolein and formaldehyde are typically <5% TLV. Considering exposure to the aerosol as a mixture of contaminants did not indicate that exceeding half of TLV for mixtures was plausible. Only exposures to the declared major ingredients -- propylene glycol and glycerin -- warrant attention because of precautionary nature of TLVs for exposures to hydrocarbons with no established toxicity. Current state of knowledge about chemistry of liquids and aerosols associated with electronic cigarettes indicates that there is no evidence that vaping produces inhalable exposures to contaminants of the aerosol that would warrant health concerns by the standards that are used to ensure safety of workplaces. However, the aerosol generated during vaping as a whole (contaminants plus declared ingredients) creates personal exposures that would justify surveillance of health among exposed persons in conjunction with investigation of means to keep any adverse health effects as low as reasonably achievable. Exposures of bystanders are likely to be orders of magnitude less, and thus pose no apparent concern.
BM-20EVALUATION OF RISK FACTORS FOR DEATH WITHIN THREE MONTHS AFTER STEREOTACTIC RADIOSURGERY FOR BRAIN METASTASES.

BACKGROUND: Stereotactic radiosurgery (SRS) is used commonly for patients with brain metastases (BM) to improve intracranial disease control. However, survival of these patients is most often dictated by the course of their systemic disease, and use of SRS for all patients with BMs is not an appropriate use of limited medical resources. We evaluated prognostic factors which may predict early death (within 90 days) after SRS. METHODS: 1427 patients with BM were treated with SRS at our institution (2000-2012) and their data are maintained in an IRB approved database. 1395 cases were included in this study. The primary end point of the study was mortality within 90 days after first SRS. Multivariate analysis was performed and a predictive model was developed to determine a prognostic index for 90-day mortality. RESULTS: Overall, 53% of patients were female, median age at diagnosis of the primary cancer was 58 years. Multiple BM was observed in 773 patients (55%), 108 patients (8%) had KPS 60 or lower at time of SRS and 1069 patients (77%) had other extra-cranial metastases. 263 patients (19%) died within 90 days after SRS. Multivariate analysis showed that KPS (p < 0.0001), extracranial metastases at SRS (p < 0.0001), number and size of BM (p = 0.003), and prior surgery (p = 0.001) were independent prognostic factors for 90-day mortality. We developed a prognostic model by assigning a weighted score to each significant factor from the multivariate analysis that is proportional to its hazard ratio. The total score for each patient was determined by summation, and four independent prognostic groups could be determined from the total scores. We found that the lowest scoring group had a 44% chance of early mortality versus 4% in highest scoring group (P < 0.0001). CONCLUSIONS: Prospective validation of this 90-day mortality risk prognostic model may provide a valuable tool for appropriate clinical resource utilization.
Etching of silicon carbide by chlorine

Abstract The reaction of Cl2 with polycrystalline β-silicon carbide was studied by the modulated molecular beam-mass spectrometric detection method. The temperature range was 300–1000 K and beam intensities between 1016 and 1017/cm2 s were employed. The sole silicon-bearing gaseous product was SiCl4, which was produced with a maximum reaction probability of 5 × 10-4 at 740 K. At higher temperatures, the reaction probability dropped precipitously, probably because of decomposition of Si-Cl surface intermediates prior to further reaction to produce the SiCl4 etch product. The CCl4 reaction product was also observed, but with a reaction probability ∼4 times lower than that of SiCl4. Buildup of an ash of unreacted carbon on the surface was demonstrated by scanning Auger microscopy. Ion bombardment during reaction had little effect on increasing product yields.
Increased colonic mucosal mast cells associated with severe watery diarrhea and microscopic colitis

A patient with microscopic colitis, clearly identifiable by its histologic characteristics, is presented in whom the histology also revealed large numbers of mast cells. The patient was treated with H1 antagonists with prompt resolution of the diarrhea. The histologic and therapeutic findings in this case suggest the diarrhea and inflammation of microscopic colitis may be mediated by the degranulation of excessive numbers of mast cells in the colon and small bowel.
Optical and Physical Effects of High Explosives

My interest in the study of the effects produced by high explosives originated in the investigation of “evidence” in a number of murders by bomb, and more especially in connexion with a most unfortunate and unusual accident which resulted in the almost instant death of a young woman who, on opening the door of the house furnace to see if the fire was burning properly, was struck by a small particle of metal which flew out of the fire and penetrated the breast bone, slitting a large artery and causing death in 2 or 3 minutes from internal haemorrhage. The particle, which was not much larger than a pin-head, was submitted to me for identification, and though its form resembled nothing with which I was familiar, I surmised that it was probably a part of a dynamite-cap or “detonator” used for exploding the dynamite charges in the mines, which, by some carelessness on the part of a miner, had been delivered intact with the coal. These detonators are spun from very thin sheet copper and consist of a tube about 5 mm. in diameter and 40 mm. in length. The head is formed into a shallow cup, as shown in cross-section in fig. 1, and the tube is charged with mercury fulminate and fired by an electrically heated wire. It seemed probable that the solid pellet of copper, recovered during the autopsy, had been formed in some way from the concave head of the detonator by the enormous instantaneous pressure developed by the detonation of the fulminate.
Cost Minimization in Networks with Discrete Stochastic Requirements

Multistage minimum-cost network-flow analysis solves many practical problems in production-inventory-distribution, marketing, personnel, and finance. Unlike previous network papers, which generally restricted themselves to a deterministic situation, this paper investigates the stochastic environment. Starting from the standard multistage network-flow problem, we create a stochastic network by permitting the node requirements to be discrete random variables with known conditional probability distributions. Our goal is to determine the minimum-expected-cost flow and thereby solve the problem. Although linear programming under uncertainty can determine this flow, it would ignore the special structure of network-flow problems that allows development of computationally efficient algorithms. In this paper, we instead exploit the underlying network structure to produce both a new structure that is not a network but maintains many of the properties of a network, and a new node that replicates flows instead of conserving them. The new nodes, called replication nodes, together with the new structure, allow the development of an efficient computational algorithm that is capable of solving problems much larger than those solvable by linear programming under uncertainty.
Self-Association and Membrane-Binding Behavior of Melittins Containing Trifluoroleucine

We have investigated the effect of trifluoroleucine substitution on the membrane-binding and tetramerization behavior of melittin. Analogues were synthesized in which Leu 9, Leu 13, and all four intrinsic leucine residues of melittin were replaced by 5,5,5-trifluoroleucine. Both the mono- and tetra-substituted melittins were found to exhibit stronger self-association and enhanced affinity for lipid bilayer membranes, compared to the wild-type peptide. The extent of the observed effects depends on the site of introduction of trifluoroleucine and, in the case of substitution at position 13, on the stereochemistry of the trifluoroleucine side chain. Analysis of the membrane association isotherms is consistent with aggregation of fluorinated melittins within the lipid bilayer. These results suggest that fluorocarbon−hydrocarbon separation, in addition to an increase in hydrophobic character, contributes to enhanced membrane binding.