cssi/SciSciGPT-SciSciNet huggingface dataset:
Community factors and hospital wide readmission rates: Does context matter?

Background The environment in which a patient lives influences their health outcomes. However, the degree to which community factors are associated with readmissions is uncertain. Objective To estimate the influence of community factors on the Centers for Medicare & Medicaid Services risk-standardized hospital-wide readmission measure (HWR)–a quality performance measure in the U.S. Research design We assessed 71 community variables in 6 domains related to health outcomes: clinical care; health behaviors; social and economic factors; the physical environment; demographics; and social capital. Subjects Medicare fee-for-service patients eligible for the HWR measure between July 2014-June 2015 (n = 6,790,723). Patients were linked to community variables using their 5-digit zip code of residence. Methods We used a random forest algorithm to rank variables for their importance in predicting HWR scores. Variables were entered into 6 domain-specific multivariable regression models in order of decreasing importance. Variables with P-values <0.10 were retained for a final model, after eliminating any that were collinear. Results Among 71 community variables, 19 were retained in the 6 domain models and in the final model. Domains which explained the most to least variance in HWR were: physical environment (R2 = 15%); clinical care (R2 = 12%); demographics (R2 = 11%); social and economic environment (R2 = 7%); health behaviors (R2 = 9%); and social capital (R2 = 8%). In the final model, the 19 variables explained more than a quarter of the variance in readmission rates (R2 = 27%). Conclusions Readmissions for a wide range of clinical conditions are influenced by factors relating to the communities in which patients reside. These findings can be used to target efforts to keep patients out of the hospital.
Do high-volume centers mitigate complication risk and reduce costs associated with performing pancreaticoduodenectomy in ethnic minorities?

Abstract Introduction Few studies examine the impact of ethnicity on post-operative outcomes and costs associated with pancreaticoduodenectomy (PD). Methods Multivariable regression (MVR) was used to perform a risk-adjusted comparison of patients within the Healthcare Cost and Utilization Project Databases undergoing PD. Results 4742 patients underwent PD. 3871 (81%) were white, 456 (10%) black, and 415 (9%) Hispanic. Black and Hispanics were less likely than whites to undergo PD in high volume centers. Blacks and Hispanics had a higher risk of select post-operative complications, prolonged lengths of stay, and high-cost outliers. When PDs done in high volume centers were evaluated separately, blacks and Hispanics had a lower adjusted-risk of any serious morbidity (OR 0.44, 95% CI [0.33, 0.57], OR 0.56, 95% CI [0.43, 0.73]) than whites but costs for PD among the three ethnic groups were statistically identical. Conclusion Racial and ethnic minorities undergoing PD are less likely to receive care at high-volume centers, are at an increased risk of post-operative morbidity, and have higher odds of being high-cost outliers than NHW.
Accessibility Evaluation of COVID-19 Vaccine Registration Websites across the United States.

This exploratory study investigated the web accessibility of 54 official COVID-19 vaccine registration websites in the US and their concordance with the WCAG 2.0 and 2.1 guidelines. We employed AChecker, WAVE, and SortSite web accessibility evaluation tools to conduct automated analyses of these websites. The results showed suboptimal compliance with WCAG 2.0 and 2.1 guidelines, as determined using the AChecker, WAVE, and SortSite tools. These shortcomings in compliance may pose difficulties to users with disabilities as they access information on the websites. Based on our findings, we offered recommendations for states and other authorities to improve the accessibility of their websites to ensure that users with disabilities can independently schedule vaccination appointments.
Fracture in Phenolic Impregnated Carbon Ablator

This paper describes the development of a novel technique to understand the failure mechanisms inside thermal protection materials. The focus of this research is on the class of materials known as phenolic impregnated carbon ablators. It has successfully flown on the Stardust spacecraft and is the thermal protection system material chosen for the Mars Science Laboratory and SpaceX Dragon spacecraft. Although it has good thermal properties, structurally, it is a weak material. To understand failure mechanisms in carbon ablators, fracture tests were performed on FiberForm®§ (precursor), virgin, and charred ablator materials. Several samples of these materials were tested to investigate failure mechanisms at a microstructural scale. Stress-strain data were obtained simultaneously to estimate the tensile strength and toughness. It was observed that cracks initiated and grew in the FiberForm when a critical stress limit was reached such that the carbon fibers separated from the binder. However, both for virgin...
Trunk and lower extremity long-axis rotation exercise improves forward single leg jump landing neuromuscular control.

Anterior cruciate ligament (ACL) injuries often involve sudden single leg loading with directional changes. Trunk and lower extremity (LE) load transfer and muscle power are directly coupled during...
Step Zero After City of Arlington

The thirty-year history of Chevron U.S.A. Inc. v. Natural Resources Defense Council, Inc.1 is a story of triumph in the courts and frustration on the part of administrative law scholars.2 Chevron‘s appeal for the courts rests in significant part on its ease of application as a decisional device. Questions about the validity of an agency‘s interpretation of a statute are reduced to two inquiries: whether the statute itself provides a clear answer and, if not, whether the agency‘s answer is a reasonable one. The framework can be applied to virtually any statutory interpretation question resolved by an agency, and its component elements—―clarity‖ and ―reasonableness‖—are sufficiently flexible to permit virtually any outcome in any particular case. Chevron also serves as the U.S. Supreme Court‘s most important admonition to lower courts not to substitute their judgment for agencies‘ on matters of policy, at least those matters that have not been resolved by Congress itself. Thus, Chevron can be invoked, when the circumstances warrant, as a symbol of judicial restraint. The frustration of many administrative law scholars rests on Chevron‘s awkwardness in discharging important functions of judicial review of agency action. Judicial review performs a variety of functions, including protecting individuals from arbitrary bureaucratic action and promoting accountability by requiring agencies to explain the reasons for their decisions. I will focus here on another important function of judicial review, which I will call boundary maintenance. Boundary maintenance includes, importantly, the principle of legislative supremacy—that agencies must respect the will of Congress. Congress is the institution best situated to allocate governmental authority among different institutions in a federal system, and when Congress has settled on a division of powers, it is critical
Listening to Fluoxetine: A Hot Message from the FLAME Trial of Poststroke Motor Recovery:

The fluoxetine for motor recovery after acute ischemic stroke study was a double blind, placebo-controlled trial examining the effects of fluoxetine in patients five- to 10 days after an ischemic stroke. The study found motor improvement to 90 days poststroke, measured as the change in the Fugl-Meyer score, was significantly greater in the fluoxetine group as compared with the placebo group, and that this finding was significant after adjusting for depression. Patients randomized to fluoxetine also had less disability (modified Rankin Scale 0-2). The study adds to the weight of data suggesting that viable strategies exist to improve patient outcomes by initiating a restorative agent, days after stroke injury is fixed. Stroke remains among the leading causes of human disability. Currently, a minority of patients can access approved reperfusion therapies, and among those so treated a substantial fraction derives limited benefit. Therapies that target restorative events have a time window measured in days-weeks and so hold the potential to help many patients with stroke.
Chapter 2 - RRKM Theory and Its Implementation

The combination of its ease and accuracy has made, and will continue to make, RRKM theory the method of choice for practical predictions of gas phase dissociation and isomerization rate coefficients. The recent and continuing advances in quantum chemical methodologies and computational efficiencies have played an important role in the transformation of RRKM theory from an empirical modeling procedure to a trulypredictive theory. The increasing accuracy of the quantum chemical estimates has resulted in numerous illustrations of the quantitative value of a priori RRKM calculations. With this new role for RRKM theory it is increasingly important to have implementations that accurately determine the effects of tunneling, of vibrational anharmonicities, of rotational nonrigidities, that employ physically meaningful representations of the transition state dividing surface, and that can be effectively coupled with quantum chemical simulations. To be of practical value these implementations must retain their efficiency, which is centered on the local nature of RRKM theory. In recent years, considerable progress has been made in many of these areas, but therestill remain a number of aspects where further developments are needed.
Modulation of Neuronal Adaptation and Cortical Associative Memory Function.

The adaptation of cortical pyramidal cells was tested during intracellular recording from brain slice preparations and the properties of this adaptation were simulated with voltage and calcium dependent potassium currents in compartmental biophysical simulations of pyramidal cells. A network of 240 simulated pyramidal cells was used to analyze the role of adaptation in cortical associative memory function. Adaptation allowed the network to make transitions between two recall states determined by different patterns of afferent input during recall. Suppression of this neuronal adaptation by cholinergic modulation allowed the network to show a sustained response to a single pattern appropriate for learning. Coupled with the cholinergic suppression of intrinsic fiber synaptic transmission, the cholinergic suppression of adaptation appears to set the appropriate network dynamics for learning new patterns. Feedback regulation of cholinergic modulation may allow the network to determine the state of learning or recall dependent upon the nature of the afferent input.
Adaptive Sensor Optimization and Cognitive Image Processing Using Autonomous Optical Neuroprocessors

Measurement and signal intelligence demands has created new requirements for information management and interoperability as they affect surveillance and situational awareness. Integration of on-board autonomous learning and adaptive control structures within a remote sensing platform architecture would substantially improve the utility of intelligence collection by facilitating real-time optimization of measurement parameters for variable field conditions. A problem faced by conventional digital implementations of intelligent systems is the conflict between a distributed parallel structure on a sequential serial interface functionally degrading bandwidth and response time. In contrast, optically designed networks exhibit the massive parallelism and interconnect density needed to perform complex cognitive functions within a dynamic asynchronous environment. Recently, all-optical self-organizing neural networks exhibiting emergent collective behavior which mimic perception, recognition, association, and contemplative learning have been realized using photorefractive holography in combination with sensory systems for feature maps, threshold decomposition, image enhancement, and nonlinear matched filters. Such hybrid information processors depart from the classical computational paradigm based on analytic rules-based algorithms and instead utilize unsupervised generalization and perceptron-like exploratory or improvisational behaviors to evolve toward optimized solutions. These systems are robust to instrumental systematics or corrupting noise and can enrich knowledge structures by allowing competition between multiple hypotheses. This propertymore » enables them to rapidly adapt or self-compensate for dynamic or imprecise conditions which would be unstable using conventional linear control models. By incorporating an intelligent optical neuroprocessor in the back plane of an imaging sensor, a broad class of high-level cognitive image analysis problems including geometric change detection, pattern recognition, and correlated feature extraction can be realized in an inherently parallel fashion without information bottlenecking or external supervision, Using this approach, we believe that autonomous control systems embodied with basic adaptive decision-theoretic capabilities can be developed for imaging and surveillance sensors to improve discrimination in stressing operational environments.« less
Experimental assessment of diazotroph responses to elevated seawater pCO2 in the North Pacific Subtropical Gyre

We examined short-term (24–72 h) responses of naturally occurring marine N2 fixing microorganisms (termed diazotrophs) to abrupt increases in the partial pressure of carbon dioxide (pCO2) in seawater during nine incubation experiments conducted between May 2010 and September 2012 at Station ALOHA (A Long-term Oligotrophic Habitat Assessment) (22°45′N, 158°W) in the North Pacific Subtropical Gyre (NPSG). Rates of N2 fixation, nitrogenase (nifH) gene abundances and transcripts of six major groups of cyanobacterial diazotrophs (including both unicellular and filamentous phylotypes), and rates of primary productivity (as measured by 14C-bicarbonate assimilation into plankton biomass) were determined under contemporary (~390 ppm) and elevated pCO2 conditions (~1100 ppm). Quantitative polymerase chain reaction (QPCR) amplification of planktonic nifH genes revealed that unicellular cyanobacteria phylotypes dominated gene abundances during these experiments. In the majority of experiments (seven out of nine), elevated pCO2 did not significantly influence rates of dinitrogen (N2) fixation or primary productivity (two-way analysis of variance (ANOVA), P > 0.05). During two experiments, rates of N2 fixation and primary productivity were significantly lower (by 79 to 82% and 52 to 72%, respectively) in the elevated pCO2 treatments relative to the ambient controls (two-way ANOVA, P < 0.05). QPCR amplification of nifH genes and gene transcripts revealed that diazotroph abundances and nifH gene expression were largely unchanged by the perturbation of the seawater pCO2. Our results suggest that naturally occurring N2 fixing plankton assemblages in the NPSG are relatively resilient to large, short-term increases in pCO2.
Formulation of an experimental substructure model using a Craig–Bampton based transmission simulator

Abstract Experimental–analytical substructuring is attractive when there is motivation to replace one or more system subcomponents with an experimental model. This experimentally derived substructure can then be coupled to finite element models of the rest of the structure to predict the system response. The transmission simulator method couples a fixture to the component of interest during a vibration test in order to improve the experimental model for the component. The transmission simulator is then subtracted from the tested system to produce the experimental component. The method reduces ill-conditioning by imposing a least squares fit of constraints between substructure modal coordinates to connect substructures, instead of directly connecting physical interface degrees of freedom. This paper presents an alternative means of deriving the experimental substructure model, in which a Craig–Bampton representation of the transmission simulator is created and subtracted from the experimental measurements. The corresponding modal basis of the transmission simulator is described by the fixed-interface modes, rather than free modes that were used in the original approach. These modes do a better job of representing the shape of the transmission simulator as it responds within the experimental system, leading to more accurate results using fewer modes. The new approach is demonstrated using a simple finite element model based example with a redundant interface.
Objective measures based on neural networks for hearing loss compensation techniques

An objective measures system has been developed to predict the results of subject-based tests for sensorineural hearing loss compensation techniques. Parameters related to the loudness level of the compensated speech signal are extracted from its frequency spectrum. These parameters are then used to train a neural network based phoneme classifier. Good prediction results have been achieved for two hearing impaired subjects. >
Notes on the breeding biology of four species of mantellid frogs from Madagascar

The breeding biologies of the mantellid frogs from Madagascar include an unusual mode of fertilization with eggs commonly laid on surfaces above water. Oviposition behavior and an understanding of clutch structure obtained only by observing oviposition and hydration of the milky white egg arrays of Guibemantis depressiceps (Boulenger 1882) are described. Multiple males are involved, and the females acted quite lethargic during the process. The much smaller egg arrays of Blommersia cf. domerguei (Guibe 1974), calling behaviors of G . liber (Peracca 1893), and nocturnal egg guarding by male Mantidactylus majori (Boulenger 1896) are also reported.
Prevalence, Pathophysiology, and Management of Androgen Deficiency in Men with Metabolic Syndrome, Type 2 Diabetes Mellitus, or Both.

The prevalence of type 2 diabetes mellitus (T2DM) and metabolic syndrome (MetS) has increased in the United States over the past 40 years. These conditions, long linked with many cardiovascular complications, have recently been linked with androgen or testosterone deficiency in men. Several pathophysiologic hypotheses exist regarding this association, with the most widely reported a relationship to obesity and insulin resistance. Several randomized trials have confirmed that when testosterone replacement therapy is given to patients with T2DM, MetS, or both, metabolic parameters such as waist circumference, hemoglobin A1c , and systolic blood pressure are significantly reduced by up to 11 cm, 1.9%, and 23 mm Hg, respectively. This has not, however, resulted in improved cardiovascular outcomes, as evidenced in studies that found increased rates of cardiovascular events following testosterone replacement therapy. In this review, we summarize the relevant literature regarding the pathophysiology and management of androgen deficiency in men with T2DM, MetS, or both.
Cyclothiazide potently inhibits γ-aminobutyric acid type A receptors in addition to enhancing glutamate responses

Ionotropic glutamate and γ-aminobutyric acid type A (GABAA) receptors mediate critical excitatory and inhibitory actions in the brain. Cyclothiazide (CTZ) is well known for its effect of enhancing glutamatergic transmission and is widely used as a blocker for α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-type glutamate receptor desensitization. Here, we report that in addition to its action on AMPA receptors, CTZ also exerts a powerful but opposite effect on GABAA receptors. We found that CTZ reversibly inhibited both evoked and spontaneous inhibitory postsynaptic currents, as well as GABA application-induced membrane currents, in a dose-dependent manner. Single-channel analyses revealed further that CTZ greatly reduced the open probability of GABAA receptor channels. These results demonstrate that CTZ interacts with both glutamate and GABAA receptors and shifts the excitation–inhibition balance in the brain by two independent mechanisms. Understanding the molecular mechanism of this double-faceted drug–receptor interaction may help in designing new therapies for neurological diseases.
Accurate ab initio treatment of low-energy electron collisions with ethylene

We report the results of a complex Kohn variational calculation of the low-energy electron scattering from ethylene, ${\mathrm{C}}_{2}$${\mathrm{H}}_{4}$. Our calculations are the first to confirm the existence of the Ramsauer-Townsend effect in a molecule which possesses a permanent quadrupole moment and suggest that such minima may be found in electron-scattering cross sections for many nonpolar molecules. The calculations also reveal a low-energy shape resonance in $^{2}$${\mathit{B}}_{2\mathit{g}}$ symmetry at 1.83 eV, in excellent agreement with both beam and swarm measurements.
An objective interpolation method for spatiotemporal distribution of marine plankton

A Lagrangian-Eulerian interpolation method for the objective analysis of marine plankton data was developed. Based on the Gauss-Markov theorem, this method takes into account the advection effect on the distribution of passive marine plankton, and yields an estimate and confidence at every interpolating point (X, y, z, t ) which is optimal in the least squares error This method was demonstrated in the analysis of plankton data collected in the California Current region during June 1993. The interpolated time series of spatial distributions of plankton revealed areas where plankton features were more permanent due to weak advection and areas where plankton features were more timedependent due to the existence of strong currents. Results show north-south transports and exchanges of plankton populations produced by the complex flow system in the California Current region This Lagrangian-Eulerian interpolation produces synoptic spat~al distributions of plankton at given times and their error fields, and can be used as a basic analytical tool to understand advection effects in plankton distributions.
The martingales of an independent increment process

Abstract A simple proof is given of the representation of martingales adapted to the sigma fields of a process with stationary, independent increments.
Milk Composition and Volume in Meadow Voles and Prairie Voles

Meadow and praire voles differ in frequency and duration of nursing. Authors examine differences in pattern of maternal investment by comparing the volume and composition of milk produced by the two species. Milk samples were collected on days 4, 8 and 12 of lactation, and analyzed for protein, fat and lactose
Regulation of Membrane Excitability in the Central Nervous System by Serotonin Receptor Subtypesa

Serotonin exerts multiple electrophysiological effects on neurons of the central nervous system. It is now known that this diversity reflects at least in part the existence of multiple serotonin receptor subtypes. An example of this occurs in the CA1 region of the hippocampus where as many as ten different serotonin receptor subtypes appear to be expressed. Recent electrophysiological studies have been able to assign specific functional roles to at least 5 of these receptors. These receptors are differentially expressed in the two different cell types present in this region, pyramidal cells and GABAergic interneurons, and mediate different effects on membrane excitability. This distribution is consistent with the different functional roles played by these cells in hippocampus. Thus the differential expression of serotonin receptor subtypes in the CA1 region allows serotonin to modify the function of hippocampal neuronal networks in a manner that is both selective and precise.
Convergent Validity of Four Computer Anxiety Scales

Intercorrelations of four scales purporting to measure computer anxiety exhibited convergent validity among college students.
Hepatocellular membrane function during chronic burn injury.

Abstract Hepatocellular membrane dysfunction, as indicated by depolarization of the membrane potential, occurs after acute injury and early bacteremia. To determine whether hepatocellular membrane dysfunction occurs in the setting of ongoing thermal injury and infection, Wistar rats were divided into four groups: (1) sham-burned, freely fed controls (FF); (2) rats sustaining ≈30% total body surface area dorsal full-thickness scald burn (Burn); (3) rats sustaining burns as in group 2 followed by immediate inoculation of 1 × 108 CFU Pseudomonas aeruginosa (Burn/Inf); and (4) sham-burned rats pair-fed to the food intake of the Burn/Inf group (PF). On the third and seventh days postburn, body and liver weights were determined. In vivo hepatocellular transmembrane potentials were measured and hepatic ATP, RNA, DNA, and protein contents were assayed. By Day 7, despite greater weight loss in the Burn/Inf group than due to starvation alone (P
Stabilization of a C7 equatorial gamma turn in DMSO-d6 by a ditryptophan crosslink.

Covalent crosslinks can control local peptide conformation. In tripeptide sequences of the general formula Cys-Xxx-Cys, cysteine disulfides have been previously shown to enforce a C7 equatorial γ-turn conformation (also referred to as an inverse γ-turn). Much less is known about the effects of dityrosine and ditryptophan crosslinks on local peptide structure. In a series of tripeptides, ditryptophan crosslinks were formed using the two-step process of acid-promoted Mannich dimerization followed by oxidative aromatization. In these peptides, with the general formula Trp-Xxx-Trp (Xxx≠Gly), ditryptophan crosslinks were found to stabilize a C7 equatorial γ-turn conformation in DMSO-d6. Rigorous support for a C7 equatorial conformation in the crosslinked sequence Trp-Pro-Trp came from a variety of 1H NMR experiments and molecular modelling. Interproton distances were derived from NOE buildups that were determined through a series of double pulsed field gradient spin echo (DPFGSE) experiments. In addition, the small temperature dependence of the i+2 NH chemical shifts (Δδ/ΔT<2 ppm/°C) provided further support for the intramolecular hydrogen bond which defines a γ-turn.
Prevalence and clinical implications of positive serum anti-microsomal antibodies in symptomatic patients with ileal pouches.

Background and aim Autoimmune disorders (AID) have been shown to be associated with chronic antibiotic-refractory pouchitis (CARP). The role of anti-microsomal antibodies in ileal pouch disorders has not been investigated. The aims of the study were to investigate the prevalence of positive anti-microsomal antibody in symptomatic patients with ileal pouches and to investigate its clinical implications.
Epidermal growth factor stimulates phosphorylation in membrane preparations in vitro.

EPIDERMAL GROWTH FACTOR (EGF) forms a complex with plasma membrane receptors in intact cells that initiates a series of biochemical events resulting in increased cell growth in vivo and in vitro1. The interaction of EGF with membrane receptors has been demonstrated in crude membrane preparations2, but no biochemical alteration of the membrane resulting from hormone binding has been detected. To clarify the molecular mechanisms regulating cell proliferation, specific biochemical reactions initiated by mitogens such as EGF need to be investigated in cell-free systems. As the human epidermoid carcinoma cell line A-431 has an extraordinarily high concentration of EGF receptors3,4 (2–3 x 106 receptors per cell), we have used a crude membrane preparation from these cells to look for an EGF-dependent alteration of membrane structure and/or function. We report here that (1) membranes may be prepared from A-431 cells that retain the ability to bind 125I-labelled EGF in a specific manner, and (2) the binding of EGF to these membranes in vitro results in a marked stimulation of the phosphorylation of endogenous proteins in the presence of [γ-32P]ATP.
Biosensing based upon molecular confinement in metallic nanocavity arrays

We describe the basis for an affinity biosensor platform in which enhanced fluorescence transduction occurs through the optical excitation of molecules located within metallic nanocavities. These nanocavities are about 200 nm in diameter, are arranged in periodic or random two-dimensional arrays, and are fabricated in 70 nm thick gold films by e-beam lithography using negative e-beam resist. The experimental results show that both periodic and randomly placed metallic nanocavities can be used to enhance the fluorescence output of molecules within the cavities by about a factor of ten. In addition, the platform provides isolation from fluorescence produced by unbound species, making it suitable for real-time detection. Finally, we demonstrate the use of the platform in the real-time detection of 20-base oligonucleotides in solution.
Re: Disparities in Utilization of Autologous Hematopoietic Cell Transplantation for Treatment of Multiple Myeloma

Abstract Costa et al. recently reported that racial disparities prevented nearly 40% of non-Hispanic blacks with multiple myeloma (MM) from undergoing stem cell transplantation (SCT), but the authors were unable to provide an explanation for the disparities because of limitations of their datasets. They hypothesized that socioeconomic status (SES) and/or insurance providers might account for the disparity. To examine the issue raised by Costa et al., we performed a secondary analysis using hierarchical multivariate logistic regression with data previously collected to determine if age at diagnosis, sex, SES, primary insurance provider at diagnosis, and comorbidity score help explain the racial disparities in SCT utilization. A model of race, age, sex, SES, insurance provider, and comorbidity score was the most accurate model in predicting stem cell utilization status (χ2[12] = 193.859; P
Cleavage of newly translated NADPH-cytochrome P-450 reductase in a rabbit reticulocyte lysate cell-free system in the absence of exogenous membranes

In a rabbit reticulocyte lysate cell-free system and using double antibody immunoprecipitation method, newly translated rat liver NADPH-cytochrome P-450 reductase (E.C. 1.6.2.4) was shown to be cleaved in the absence of exogenous membranes. Reductase having a Mr = 78,000 was shown to be converted to a Mr = 67,000 upon incubation with either lysate or antisera. Peptide maps of 78,000 dalton reductase and 67,000 dalton protein were identical except for three additional peptides present in the 78,000 dalton reductase map. The cleavage activity associated with the antisera could be prevented by using the IgG fraction, while that associated with the lysate was inhibited by using the protease inhibitors leupeptin, pepstatin or bestatin.
Bilateral absence of the pars interarticularis of C2: developmental or post-traumatic abnormality?

A 19-year-old male was diagnosed with bilateral absence of C2 pars interarticularis incidentally after a motor vehicle accident. Plain radiography, cross-sectional CT, and 3D CT findings of this case are presented. The differential diagnosis and possible etiologies including remote child abuse are discussed in detail.
Chiral recognition in complexation of guests by designed host molecules

ABSTRACT Host molecules have been designed and synthesized to selectively complex and lipophilize guest molecules. Examples of the use of the following binding interactions are given: hydrogen bonding, ion pairing, cation to n-electrons, carbonyl to n-electrons and pi-pi bonding. Multiheteromacrocycles have been prepared whose association constants with tert -butylammonium salts in chloroform range from 6 M -1 . Host molecules with built-in counterions have been prepared that selectively complex and lipophilize metal and alkylammonium cations. Locations of complementary binding sites and non-complementary steric barriers provide for selective binding by host molecules of candidate guest molecules. Locations of appropriate chiral barriers and multiple complexing sites in guest compounds have led to the complete optical resolution of host compounds by optically active amino acids, and of amino acid esters by optically active host compounds. Ratios of association constants for diastereomeric complexes in excess of ten have been obtained. A molecular basis for designing an amino acid resolving machine has been developed.
Studies of GI Bleeding With Scintigraphy and the Influence of Vasopressin

The management of patients with gastrointestinal (GI) bleeding depends on accurate localization of the site of hemorrhage. Endoscopy and arteriography, although successful in achieving this goal in the majority of patients, are invasive and have other shortcomings. The introduction of the 99mTc-sulfur colloid technique has greatly simplified the evaluation and management of these patients. This test is useful in detecting and localizing the bleeding site in the lower GI tract. Scintigraphy is now used as the initial study of choice in patients with rectal bleeding. Advances made in angiography and nuclear medicine techniques also have resulted in improved management of patients. Conservative approaches succeed in controlling hemorrhage in most patients. Vasopressin is the most widely tested agent and has been adopted by many as the preferred preparation for this purpose. Before the introduction of the 99mTc-sulfur colloid technique, angiography was used to monitor the effectiveness of this drug, whether administered intravenously or intraarterially. With the use of scintigraphy and intravenous administration of vasopressin, these patients now can be managed noninvasively. Only when the intravenous Pitressin infusion fails to stop hemorrhage, is the intraarterial approach considered. Surgery is used as a last resort when these measures fail to stop the bleeding.
Metabolism of the Chelating Agent Diethylenetriamine Pentaacetic Acid (C14DTPA) in Man.

Intravenously injected C14DTPA in man is quantitatively excreted in urine in 24 hours. Following oral ingestion of C14DTPA, the major portion of the chelate passes unabsorbed through the intestine. However, the presence of the C14 chelate in urine is evidence for absorption of some, although small, amounts of the chelating agents. The metabolism of DTPA was shown to be similar to that of EDTA.
Case-based reasoning to help educators design with Web 2.0

This study proposes the use of case-based reasoning to help educators design with Web 2.0. Principles for designing a web-enhanced case-based activity (CBA) were used to design an online professional development course for a group of 16 in-service educators. The Learning in Context model was used as a scaffold to help participants in their design of activities. Formative evaluation points toward the utility of this approach, and rich description is provided to help readers assess the findings. Findings related to the use of CBA design principles include: the possibility of using open resources to build case libraries; the importance of using expert cases analogous to the needs of participants; the importance of direct and soft scaffolding; the need for feedback, reflection and design iteration; and the perceived usefulness of the Learning in Context model as a scaffold. An unexpected finding was how hands-on familiarity with the tools appeared to be a prerequisite for participants to engage in the expert ...
Heterogeneity and Collective Management: Evidence from Common Forests in Himachal Pradesh, India

Summary This paper conducts a statistical investigation into the impact of differences in economic benefits, wealth, and social classes within the community on collective management of forests. There are two key results. First, social parochialism is not a pre-requisite for collective management of forests. Moderate levels of social diversity are associated with low collective management, but at high levels of social diversity, collective management is high. Second, moderate wealth heterogeneity is beneficial; however, at high levels and in the presence of benefit heterogeneity, it decreases collective management. Similarly, benefit heterogeneity reduces collective management if wealth heterogeneity also exists. These results run counter to the dominant understanding of heterogeneity but may be seen as alternate explanations under a specific socioeconomic context.
Barriers to Completion of Advance Care Directives among African Americans Ages 25–84: A Cross-Generational Study

Prior studies conducted in the area of Advance Care Directive document completion in African Americans have primarily targeted the elderly who are either institutionalized in skilled nursing facilities or are members of faith communities. Few studies have been done concerning barriers to Advance Care Directive document completion that include non-elderly African Americans. The purpose of this study was to identify the common barriers to advance care directive document completion across generations of African Americans ages 25–84. Using convenience sampling among various Baptist denominations of the African-American faith community of Buncombe County, North Carolina, 40 individuals ranging in age from 25–84 participated in multiple focus group sessions. Findings revealed participants shared three common barriers: 1) surrogate decision-making, 2) lack of education concerning advance care directive discussions and completion and 3) fear and denial. Also revealed were barriers that varied across generations: ...
Molecular profiling of a mouse model for metastatic breast carcinoma

Breast cancer is among the most common human cancers. One of the significant predictors of prognosis is distant metastasis. As cancer is the consequence of a broad dysregulation of cell signaling pathways, the ability of cells to metastasize may be due to changes in a limited number of pathways related to invasiveness and metastasis. Our study focuses on gaining a better understanding of these pathways using a mouse model for mammary tumor metastasis. We are working with two transplantable mouse mammary tumor lines with significant differences in metastatic potential. Met-1 tumors develop 100% pulmonary metastases while Db-7 tumors exhibit significantly fewer pulmonary metastases (9%). In order to extract genes differentially expressed in both Met-1 and Db-7, we performed two suppression subtractive hybridization (SSH) experiments. From each of the subtracted libraries, 2600 clones were PCR-amplified and arrayed. By fluorescently labeling the unsubtracted Met-1 and Db-7 libraries and hybridizing them onto the microarray, we were able to demarcate the truly differentially expressed genes. Clones found to be greater than two-fold differentially expressed were then sequenced for identification. Differential expression of each gene was verified by RT-PCR, Northern blot, and Western blot. In order to determine the function of a subset of these genes, anti-sense and sense constructs were introduced into cell lines derived from these tumors. Migration assays were performed and the metastatic potential of each gene was assessed. We have identified several interesting genes that are both differentially and functionally important for the metastatic phenotype in this model.
Prediction of mass transfer rate in fibrous and granular media using packing permeability

Abstract Mass transfer in randomly packed fibrous and granular media is investigated theoretically for the case of high Pe numbers, where the mass transfer boundary layer is much thinner than the heat transfer boundary layer. The mass transfer rate is correlated with the packing permeability, which contains the major information of packing characteristics, porosity and element size which can all be measured by simple experiments. The correlation describes available numerical and experimental data with very good agreement.
Hydrazinoacridine staining of proteins and glycoproteins in polyacrylamide gels

Abstract The histochemical method for staining polyaldehydes in tissue sections with p-hydrazinoacridine has been adapted for use in polyacrylamide gels. While staining of histological preparations was reported to be specific for polyaldehydes and independent of bisulfite, both glycoproteins (β chain of haptoglobin) and nonglycoproteins (lysozyme and α chain of haptoglobin) were stained following periodate oxidation, and satisfactory results were highly dependent on the presence of bisulfite. Hydrazinoacridine staining of periodate-treated gels produced an extremely sensitive fluorescent labeling of the haptoglobin β chain and also stained haptoglobin α chain and lysozyme. The proteins could be visualized under visible light as yellow bands which were scanned spectrophotometrically at 440 nm. The β chain of haptoglobin could be subjectively distinguished from the nonglycoproteins both by differential intensity of staining with hydrazinoacridine and Coomassie brilliant blue and by the yellow nature of the fluorescence. The sensitivity of hydrazinoacridine staining of the β chain of haptoglobin compared favorably to that of the commonly used periodic acid-Schiff staining procedures and provided the advantage that nonglycoproteins in complex mixtures could be localized in the gels.
A NEW APPROXIMATION FOR FISHER'S Z

Summary As the sample size increases, the coefficient of skewness of the Fisher's transformation z= tanh-1r, of the correlation coefficient decreases much more rapidly than the excess of its kurtosis. Hence, the distribution of standardized z can be approximated more accurately in terms of the t distribution with matching kurtosis than by the unit normal distribution. This t distribution can, in turn be subjected to Wallace's approximation resulting in a new normal approximation for the Fisher's z transform. This approximation, which can be used to estimate the probabilities, as well as the percentiles, compares favorably in both accuracy and simplicity, with the two best earlier approximations, namely, those due to Ruben (1966) and Kraemer (1974). Fisher (1921) suggested approximating distribution of the variance stabilizing transform z=(1/2) log ((1 +r)/(1r)) of the correlation coefficient r by the normal distribution with mean = (1/2) log ((1 + p)/(lp)) and variance =l/(n3). This approximation is generally recognized as being remarkably accurate when ||Gr| is moderate but not so accurate when ||Gr| is large, even when n is not small (David (1938)). Among various alternatives to Fisher's approximation, the normalizing transformation due to Ruben (1966) and a t approximation due to Kraemer (1973), are interesting on the grounds of novelty, accuracy and/or aesthetics. If r= r/√ (1r2) and r|Gr = |Gr/√(1|Gr2), then Ruben (1966) showed that (1) gn (r,|Gr) ={(2n5)/2}1/2rr{(2n3)/2}1/2r|GR, {1 + (1/2)(rr2+r|Gr2)}1/2 is approximately unit normal. Kraemer (1973) suggests approximating (2) tn (r, |Gr) = (r|GR1) √ (n2), √(11r2) √(1|Gr2) by a Student's t variable with (n2) degrees of freedom, where after considering various valid choices for |Gr1 she recommends taking |Gr1= |Gr*, the median of r given n and |Gr.
Investigation of solvation in lithium ion battery electrolytes by NMR spectroscopy

Abstract The solvation of LiPF6 by carbonate solvents (EC, DMC, and DEC) was investigated via 13C NMR chemical shift and 1H NMR diffusion coefficient experiments. The gradual addition of LiPF6 into a ternary solvent mixture results in a larger change in the chemical shift of EC than DMC or DEC suggesting that EC binds Li+ more strongly than DEC or DMC. The self diffusion coefficient of the carbonate solvents provides additional support for EC binding Li+ more strongly than DEC or DMC. Variable temperature NMR spectroscopic investigations support an increase in EC binding at low temperature and an enthalpic preference for the binding of EC to Li+.
Multi-Objective Multi-User Scheduling for Space Science Missions

We have developed an architecture called MUSE (Multi-User Scheduling Environment) to enable the integration of multi-objective evolutionary algorithms with existing domain planning and scheduling tools. Our approach is intended to make it possible to re-use existing software, while obtaining the advantages of multi-objective optimization algorithms. This approach enables multiple participants to actively engage in the optimization process, each representing one or more objectives in the optimization problem. As initial applications, we apply our approach to scheduling the James Webb Space Telescope, where three objectives are modeled: minimizing wasted time, minimizing the number of observations that miss their last planning opportunity in a year, and minimizing the (vector) build up of angular momentum that would necessitate the use of mission critical propellant to dump the momentum. As a second application area, we model aspects of the Cassini science planning process, including the trade-off between collecting data (subject to onboard recorder capacity) and transmitting saved data to Earth. A third mission application is that of scheduling the Cluster 4-spacecraft constellation plasma experiment. In this paper we describe our overall architecture and our adaptations for these different application domains. We also describe our plans for applying this approach to other science mission planning and scheduling problems in the future.
Genomic characterization of Helicobacter hepaticus: ordered cosmid library and comparative sequence analysis

Helicobacter hepaticus is an important pathogen in laboratory mice and induces the development of liver tumors and gastrointestinal disease in susceptible strains of mice. In this study, a miniset of 36 cosmid clones from a genomic library of H. hepaticus was ordered and grouped into four large contigs representing approximately 1 Mb of the H. hepaticus genome using PCR, DNA sequencing, Southern and dot-blot hybridization and pulsed-field gel electrophoresis. From the 200–300 terminal nucleotide sequences of 38 cosmid clones, 56 coding regions were predicted, of which 51 were found to have orthologs in the public databases and five appeared to be unique to H. hepaticus. Of these 51 genes, 36 have orthologs in Helicobacter pylori and 25 display the highest sequence similarity to H. pylori. However, chromosomal positions of these genes are not conserved between these two helicobacters. In addition, 10 H. hepaticus genes had the highest sequence similarity to orthologs in Campylobacter jejuni. The GC content in a randomly selected 21-kb H. hepaticus genomic sequence was 35.8%, which approximates the average between H. pylori (39%) and C. jejuni (30.6%). These results demonstrate that: (1) H. hepaticus is more closely related to H. pylori than C. jejuni; (2) significant genomic alterations exist between H. hepaticus and H. pylori, including gene organization, protein sequences and GC content, probably in part due to specific adaptation to distinct ecological niches.
Graphene Role as Platinum Support for CO and Formic Acid Electrooxidation

The direct methanol fuel cell (DMFC) is a promising power source for electronic applications due to its high efficiency and compactness. To improve the efficiency, many support materials have been developed. We investigated uniform graphene nanoflake films as a support for catalytic Pt nanoparticles in direct carbon monooxide and formic acid electro-oxidation. Pt nanoparticles were deposited on the surface of graphene films with chemical reduction method. Chemical functionalization of graphene with ethylenediamine enables Pt nanoparticles mobilize on graphene uniformly. By simply changing the loading amount of Pt precursor, various particle sizes were achieved. The particle size of Pt plays prominent role in fuel cell test. The electrochemically active surface area of different sample are 6.3 (5 wt% Pt/G), 4.1 (20 wt% Pt/G), and 3.0 (50 wt% Pt/G) cm2mg-1 corresponding to the particle size 3±1nm, 10±2nm, 20±2nm respectively. The results obtained are ascribed to a uniform network made of 2-4 nm Pt monolayer nanopaticles on the surface of graphene flakes. Graphene will play significant role in developing next-generation advanced Pt based fuel cells and their relevant electrodes in the field of energy.