cssi/SciSciGPT-SciSciNet huggingface dataset:
MO-E-L100J-07: Multiplexing Radiography for Ultra-Fast Computed Tomography: A Feasibility Study

Purpose: Current CT scanners collect the projection images by a step‐and‐shoot process using a single x‐ray source. The inefficient serial data collection scheme severely limits the data collection speed. Multiplexing technique, which has been widely adopted in communication devices, holds the promise to significantly increase the data throughput. It however, has not been applied to x‐ray radiography, mainly due to limitations of the current x‐ray source technology. Method and Materials: We demonstrated the feasibility of multiplexingradiography technique based on the frequency division multiplexing (FDM) principle and the multi‐pixel x‐ray technology. The carbon nanotube based field emission multi‐pixel x‐ray source can generate spatially and temporally modulated x‐ray radiation. During the multiplexingimaging process, all the x‐ray pixels were turned on simultaneously with each beam modulated at a different frequency. The superimposed x‐ray signals were captured by an x‐ray detector and then demultiplexed to recover the original nine projection images from different view angles. Results: In general a factor of N/2 (N= total number of images) increase in the speed can be achieved using the multiplexing scheme. This becomes significant when N is large, for example for clinical CT scanners which use ∼1000 views per gantry rotation. On the other hand, if the total imaging time and x‐ray dose are kept the same as used in the sequential process, then the x‐ray power, i.e. the tube current, can be reduced by a factor of N/2 by multiplexing because the exposure time per image is now longer. Conclusion: In summary, we show the feasibility of multiplexingradiography that enables simultaneous collection of multiple projection images. Overall the experiment has sufficiently demonstrated the efficiency of multiplexing for data collection compared to the current serial approach. It has the potential to significantly increase the imaging speed for CT scanning without compromising the imaging quality.
Physiological effects of chronic and acute application of N-methyl-D-aspartate and 5-amino-phosphonovaleric acid to the optic tectum of Rana pipiens frogs.

Abstract Visually elicited activity contributes to the formation of orderly connections in the optic tectum of frogs. Glutamate receptors of the N -methyl- d -aspartate class participate in this process. Blocking those receptors interferes with activity-dependent refinement of maps in normal frogs and of ocular dominance bands in surgically produced animals with three eyes. Chronic application of N -methyl- d -aspartate sharpens the bands. The possibility that 5-amino-phosphonovaleric acid depresses tectal responsiveness was motivation for studying the effects of 5-amino-phosphonovaleric acid and N -methyl- d -aspartate applied both chronically and acutely. We evaluated tectal responsiveness to visual input by presenting flashes of light to one eye and recording responses in the ipsilateral tectal lobe. This method reveals the output of the tectal cells contralateral to the stimulated eye. These cells project via the nucleus isthmi to the opposite tectal lobe. We also mapped the receptive field dimensions of the crossed isthmotectal axons. Our results show that acute topical application of 500 μM or 1 mM N -methyl- d -aspartate dramatically increases spontaneous activity, while 100 μM N -methyl- d -aspartate causes little change. Chronic treatment with N -methyl- d -aspartate at a low dose (estimated to be in the micromolar range) shown to influence retinotectal mapping, reduces response latencies but produces no statistically significant changes in tectal cell firing rates or receptive field size. Acute application of 5-amino-phosphonovaleric acid produces complex results: 10 μM produces no changes in firing, 100 μM 5-amino-phosphonovaleric acid decreases firing, and doses of 500−100 μM increase the firing. Chronic micromolar 5-amino-phosphono-valeric acid, at doses capable of blocking activity-dependent refinement of retinotectal maps, decreases spontaneous firing and the latency of visually evoked bursts but otherwise produces no notable changes in tectal cell responses. Our data support the hypothesis that chronic treatment with N -methyl- d -aspartate and 5-amino-phos-phonovaleric acid influence retinotectal development by affecting the N -methyl- d -aspartate receptor specifically and not by causing overall changes in tectal activity.
Liver function and morphology after resuscitation from severe hemorrhagic shock with hemoglobin solutions or autologous blood

Objective To test the effects of three hemoglobin solutions on liver function and hepatic morphology after resuscitation from severe hemorrhagic shock.Design Prospective study.Setting Laboratory.Subjects Thirty-three beagle dogs.Intervention Hemorrhagic shock was induced in anesthetized dogs by remo
How to Use Tests for Univariate Normality to Assess Multivariate Normality

Abstract The assumption of multivariate normality (MVN) underlies many important techniques in multivariate analysis. In the past 50 years, over 50 tests of this assumption have been proposed. However, for various reasons, practitioners are often reluctant to address the MVN issue. In this article, several techniques for assessing MVN based on well-known tests for univariate normality are described and suggestions are offered for their practical application. The techniques are illustrated using two previously published sets of real-life data. In one of the examples it is shown that simply testing each of the marginal distributions for univariate normality can lead to a mistaken conclusion.
Synthesis of α-L-rhamnosyl ceramide and evaluation of its binding with anti-rhamnose antibodies.

Abstract An α- l -rhamnosyl ceramide ( 1 , α- l -RhaCer) has been prepared that was recognized by anti- l -rhamnose (anti-Rha) antibodies. During these studies we explored the use of an α- l -rhamnosyl thioglycoside and a trichloroacetimidate as a glycosyl donors. Subsequently, the acceptors desired for glycosylation, 3- O -benzoylazidosphingosine or 3- O -alloxycarbonylsphingosine, were prepared from d -xylose. The thioglycoside donor, 2,3,4-tri- O -acetyl-1-(4-tolyl)thio-α- l -rhamnopyranoside, and the trichloroacetimidate donor, 2,3,4-tri- O -acetyl-1-(2,2,2-trichloroethanimidate)-α- l -rhamnopyranoside, were synthesized in 50% and 78% yield overall, respectively. The synthesis of the glycosylation acceptor employed an addition–fragmentation olefination that was successfully carried out in 53% yield. With the successful synthesis of key intermediates, α- l -RhaCer ( 1 ) was prepared without any insurmountable obstacles. Anti-Rha antibodies were prepared in BALB/c mice by immunizing them with rhamnose-ovalbumin (Rha-Ova) with Sigma Adjuvant System (SAS) and the anti- l -Rha antibodies were isolated from the blood sera. Liposomes and EL4 tumor cells were used as model systems to demonstrate the ability of 1 to insert into a lipid bilayer. The interaction of the liposomes or the EL4 cells with α- l -RhaCer ( 1 ) and anti-Rha antibodies were investigated by fluorescence microscopy and flow cytometry, respectively, to confirm the ability of glycolipid 1 to be displayed on the tumor cell surface as well as the ability to be recognized by anti-Rha antibodies.
Toward a tripartite factor structure of mental health: subjective well-being, personal growth, and religiosity.

According to recent research findings, the domain of psychological well-being may be represented by 2 basic factors: subjective well-being (e.g., happiness, life satisfaction) and personal growth (e.g., self-actualization, a sense of meaningfulness). This study tested the hypothesis that in addition to those 2 factors, a 3rd basic factor is necessary to adequately describe the ways in which people search for well-being. That factor is a type of religiosity that is based on other-centeredness and self-renunciation. A sample of 242 undergraduate and graduate students completed 10 measures of psychological well-being that resulted in 21 scales and subscales. Principal components analyses provided initial support for a tripartite model of psychological well-being. Results also suggested that current measures of personal growth may measure either the autonomy or mature social relationships components of the construct.
Standard measures of executive function in predicting instrumental activities of daily living in older adults.

Objective The purpose of this study was to examine the ability of specific, commonly used neuropsychological tests of executive function to predict functional status among a group of elderly subjects. Methods Fifty study participants underwent a brief neuropsychological evaluation of executive functions and assessment of instrumental activities of daily living (IADL). Results A multiple stepwise regression analysis indicated that executive function tests accounted for 54% of the variance in functional status. An examination of the standardized regression coefficients revealed that Trail Making Test-Part B and the Wisconsin Card Sorting Test were the only two of the five executive function tests that significantly predicted functional status. These executive function measures contributed significantly to the prediction of functional status even after statistically controlling for age, sex, and education. Conclusion Thus, the common clinical measures of executive function are useful in predicting functional status in older adults. Copyright © 2002 John Wiley & Sons, Ltd.
Managed Care and Mental Health Services: How We Got to Where We Are:

Abstract In September 1997, the National Alliance for the Mentally Ill issued a national report card asserting that managed care companies are falling short of their promise to deliver high-quality care to people with mental illnesses. This article traces how mental health care has evolved from the overbuilding of psychiatric facilities in the mid and late 1980s to a situation in which millions of mentally ill Americans cannot receive adequate care. It traces events that led to the unprecedented boom in psychiatric care through the 1980s to the place where health care reform has evolved. The disparity between insurance coverage of mental health care services and general medical care services is discussed, and the legislative outcome of recent mental health reform is described. Finally, implications for nursing and recommendations for action are considered.
Direct calculation of binding energies of inner-shell electrons in molecules

Abstract The calculation of binding energies of molecular inner-shell electrons as the difference between the SCF energies of ground state and inner-shell hole state is discussed. A flexible Gaussian orbital basis set gives good results for the 1s binding energies in Ne and CH 4 , where unambiguous data from other sources exist for comparison. Calculated predicted 1s binding energies for the heavy atoms in first row hydrides are (in eV): BH 3 , 197.5; CH 4 , 291.0; NH 3 , 405.7; H 2 O, 539.4; HF, 693.3.
Regulatory T cells are recruited in the infarcted mouse myocardium and may modulate fibroblast phenotype and function

Regulatory T cells (Tregs) play a pivotal role in suppressing immune responses regulating behavior and gene expression in effector T cells, macrophages, and dendritic cells. Tregs infiltrate the infarcted myocardium; however, their role the inflammatory and reparative response after myocardial infarction remains poorly understood. We used FoxP3EGFP reporter mice to study Treg trafficking in the infarcted heart and examined the effects of Treg depletion on postinfarction remodeling using an anti-CD25 antibody. Moreover, we investigated the in vitro effects of Tregs on cardiac fibroblast phenotype and function. Low numbers of Tregs infiltrated the infarcted myocardium after 24–72 h of reperfusion. Treg depletion had no significant effects on cardiac dysfunction and scar size after reperfused myocardial infarction but accelerated ventricular dilation and accentuated apical remodeling. Enhanced myocardial dilation in Treg-depleted animals was associated with increased expression of chemokine (C-C motif) ligand 2 and accentuated macrophage infiltration. In vitro, Tregs modulated the cardiac fibroblast phenotype, reducing expression of α-smooth muscle actin, decreasing expression of matrix metalloproteinase-3, and attenuating contraction of fibroblast-populated collagen pads. Our findings suggest that endogenous Tregs have modest effects on the inflammatory and reparative response after myocardial infarction. However, the anti-inflammatory and matrix-preserving properties of Tregs may suggest a role for Treg-based cell therapy in the attenuation of adverse postinfarction remodeling.
Characterization of pre- and postsynaptic dopamine receptors in Lymnaea

Abstract 1. 1. The effects of dopamine and several synthetic agonists and antagonists were studied using two identified neurons of the snail Lymnaea stagnalis . 2. 2. In both the buccal-2 (B-2) neurons and the pedal giant (RPeDl) neuron dopamine elicited a hyperpolarizing response at least partly due to potassium efflux. RPeDl is itself dopaminergic, implicating autoreceptors in its response to dopamine. 3. 3. The following agents were tested: agonists—LY171555, pergolide, SKF38393, (−)−3-PPP, R(−)NPA and dopamine; antagonists-SCH23390, sulpiride, and metaclopramide. Dibutyryl cAMP was applied to determine whether the response is cAMP-mediated. 4. 4. Results indicate that the pharmacological profiles of dopamine receptors on these neurons are inconsistent with those of either D-1, D-2 or autoreceptors in mammals.
Developmental Neuroimaging Studies of OCD: The Maturation of a Field

It is informative to reflect on the maturation of the modern psychiatric neuroimaging field, which now spans more than three decades. During this time, structural neuroimaging has progressed from crude computed tomographic methods to refined magnetic resonance imaging (MRI) approaches. The evolution in this domain began with gross measurements of brain and ventricles, advanced to segmentation of circumscribed subcortical structures, then cortical parcellation, and more recently cortical thickness and white matter tract evaluation by diffusion tensor imaging. In tandem, we have seen a technical revolution from manual methods to automated capabilities, making studies of very large numbers of subjects and ultimately “movies” of the developmental process finally feasible. 1 Similarly, in functional neuroimaging, early studies involved methods reliant on radiotracers in the context of resting or neutral state
Differences in Familial Incidence of Mortality from “Blue Comb” Disease

Abstract THE diagnosis of blue comb on the basis of clinical symptoms, and gross and microscopic lesions, is fairly definite when the disturbance involves several birds in a population. It is much less so when only an individual bird is available for autopsy and the case history does not indicate a generalized flock condition. Blue comb, as a specific disease entity, has been recognized for several years and can cause considerable loss in the form of mortality, reduced production, and often from the failure of laying flocks to regain previous levels of performance. It apparently is not limited to any age group or season of the year, although many of the outbreaks occur among maturing pullets during the hot summer weather. CASE HISTORY Blue comb, as such, has not been a problem in the departmental flock at Cornell University for several years. About 1940, this disease affected newly-housed White Leghorn pullets, . . .
Engineering students’ perceptions of engineering specialties

Abstract The field of engineering is defined by a number of specialty areas, thus most engineering students must decide upon an educational specialty track within the engineering major. Data on familiarity with, and perceptions of similarity among 11 engineering specialties were collected from 129 undergraduate engineering students from a public urban university. Similarity data were collected by way of a paired comparison task, and multidimensional scaling techniques were used to map these data into spatial representations. A three-dimensional solution was selected. Analysis of variance procedures also were used to examine differences in perceptions of engineering specialties by gender, ethnicity, commitment to career choice, and career decision-making self-efficacy. Results indicated that female students rated engineering specialties as more prestigious than male students, and students with a more dogmatic stance towards career rated engineering as relatively exclusive to men.
Using the Spina Bifida Life Course Model in Clinical Practice: An Interdisciplinary Approach

The Life Course Model for patients, families, caregivers, teachers, and clinicians was developed with support by the National Spina Bifida Program, National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, for individuals with spina bifida. The Life Course Model facilitates a developmental approach to assessment and intervention along life's trajectory. This Life Course Model provides information about key developmental milestones for particular age groups, validated assessments that can be performed by clinicians or teachers to determine if milestones have been reached, useful suggestions for intervening in creative ways at each step, and evidence-based references. In this article, the authors introduce the viewpoints of several key clinicians who are involved in the care of individuals with spina bifida and how the Life Course Model can assist them, their patients, and their families in the process of assessment, intervention, collaboration with other clinicians, and follow-up. A case study is used to demonstrate the experience of comprehensive and collaborative management in transitioning a child and his family from infancy to adulthood.
Genetic counselors' current use of personal health records-based family histories in genetic clinics and considerations for their future adoption

Given the widespread adoption of electronic medical records and recent emergence of electronic family history tools, we examined genetic counselors’ perspectives on the emerging technology of the personal health record (PHR)-based family history tool that links to an electronic medical record (EMR). Two-hundred thirty-three genetic counselors responded to an on-line survey eliciting current use of electronic family history (EFH) tools and familiarity with PHR-based family history tools. Additionally, after being shown a series of screen shots of a newly developed PHR-based family history tool based on the U.S. Surgeon General’s My Family Health Portrait (United States Department of Health and Human Services 2009), participants were surveyed about the perceived usefulness, ease of use, and impact on current workflow that this kind of tool would have in their practices. Eighty-three percent reported that their institution has an EMR, yet only 35 % have a dedicated space for family history. Eighty-two percent reported that less than 5 % of their patients have a PHR, and only 16 % have worked with patients who have a PHR. Seventy-two percent or more agreed that a PHR-based family history tool would facilitate communication, increase accuracy of information, ensure consistency in recording information, increase focus on actual counseling, reduce repetitive questions, improve efficiency, and increase the legibility and clarity. Our findings suggest that participants were familiar with existing EFH tools, but that the majority did not use them in practice. Genetic counselors’ adoption of such tools is limited due to non-existence of this kind of technology or inability to integrate it into their clinics. They are also strongly in favor of adopting a PHR-based family history tool in genetics clinics, but have practical concerns that must be addressed before the tool can be implemented.
Morphology evolution and luminescence properties of porous GaN generated via Pt-assisted electroless etching of hydride vapor phase epitaxy GaN on sapphire

Porous gallium nitride (PGaN) is produced by Pt-assisted electroless etching of hydride vapor phase epitaxy (HVPE)–GaN. Ultrathin Pt films are sputtered onto the GaN surface, and etching is carried out in a 1:2:1 solution of CH3OH:HF:H2O2. The evolution of the morphology proceeds by first forming a network of small pores, after which a ridge-trench morphology evolves, with ridges separated by a porous network in trenches between the ridges. As the etch progresses further the ridges evolve to a maximum size and then start to disappear. The formation and evolution of the ridge-trench morphology is explained by the presence of two different etch rates, an enhanced etch rate which generates the porous network and a slower etch rate that leads to the terraces of the ridge morphology. The rate at which the morphology evolves depends on the carrier concentration, with more heavily doped samples etching faster. In all cases, the final depth of the trenches between ridges is independent on the thickness of the sta...
Multiplet analysis at Coso geothermal

Abstract We have searched the Coso geothermal field (CGF) for microseismicity in seismic doublets, co-located hypocenters that appear to have nearly identical waveforms. Using 1085 high-quality events from 1993 to 1994, we identified numerous doublets, some occurring within minutes of each other. We subdivided hypocentral data into spatial clusters to reduce the computational burden and evaluated multiple cross-correlation pairs, assigning scores to each pair. As an example, one spatial cluster includes 183 events yielding 96 high-correlation (>0.6) paired events. To isolate potential multiplets, equivalence class analysis and cluster analysis routines were used. Among the 96 high-correlation pairs, 24 equivalence classes have been isolated. While most of these are doublets, 8 classes include 3 or more cluster members and one class includes 16 members. Relative locations were calculated using phase shifts between corresponding events. Detailed analysis of hypocenter relocations shows elongate, vertical structure with apparent random temporal variations. The multiplets do not appear to be true repeating events; rather, they are clusters of small, nearly identically oriented ruptures, perhaps representing swarms of fractures activated by fluid-pressure fluctuations. Using the small volumes encompassing each multiplet, we estimate fracture densities measure between 0.02 and 0.4 m −1 and are largest near injection wells.
Inferring and Enforcing Relative Constraints in SLAM

Most algorithms for simultaneous localization and mapping (slam) do not incorporate prior knowledge of structural or geometrical characteristics of the environment. In some cases, such information is readily available and making some assumptions is reasonable. For example, one can often assume that many walls in an indoor environment are rectilinear. In this paper, we develop a slam algorithm that incorporates prior knowledge of relative constraints between landmarks. We describe a “Rao-Blackwellized constraint filter” that infers applicable constraints and efficiently enforces them in a particle filtering framework. We have implemented our approach with rectilinearity constraints. Results from simulated and real-world experiments show the use of constraints leads to consistency improvements and a reduction in the number of particles needed to build maps.
Dynamical consequences of fast-rising, slow-decaying synapses in neuronal networks

Synapses that rise quickly but have long persistence are shown to have certain computational advantages. They have some unique mathematical properties as well and in some instances can make neurons behave as if they are weakly coupled oscillators. This property allows us to determine their synchronization properties. Furthermore, slowly decaying synapses allow recurrent networks to maintain excitation in the absence of inputs, whereas faster decaying synapses do not. There is an interaction between the synaptic strength and the persistence that allows recurrent networks to fire at low rates if the synapses are sufficiently slow. Waves and localized structures are constructed in spatially extended networks with slowly decaying synapses.
Digitally Tunable Active Filter Biouads

Canonical controllability equations for independent pole/zero frequency, bandwidth and q-factor are formulated for biquadratic transfer functions. Corresponding root loci for the digital tuning case are also shown. Elementary building blocks of programmable analog co'nputer type active filters (integrators and summers) using multiplying digital -to-analog converters are introduced. Canonical controllability of two important state variable biquads (KHN and Thomas-Tow) is evaluated.
Relating Local Nanomechanical Response of Cells to Intracellular Forces and Cell Morphology

Mechanical processes regulate cell physiology primarily at the molecular level, but current techniques have difficulty achieving mechanical contrast at molecular length scales. We recently developed an AFM-based tool that can probe mechanical properties of living cells with nanoscale resolution. However, the measurements we obtained at the nanoscale are hard to reconcile with the viscoelastic view of cell mechanical behavior. We predominantly observe elastic response with little hysteresis in the corresponding force distance curves. In addition, force distance curves are surprisingly linear, which would not be the case for viscoelastic materials indented by conical AFM tips. We have created a model for the nanomechanical response of cells that takes intracellular forces into account. The model not only explains the near-elastic response and the linearity of force distance curves, but also makes quantitative predictions about cell shape and its relationship to the local nanomechanical response. We experimentally tested and verified these predictions on cells exhibiting different morphologies. In addition to these predictions, the model allows determining intracellular forces from the AFM images, such as tension across actin fibers and cortex tension. This work expands the existing cell mechanical models into the nanoscale and enables AFM to obtain physiologically relevant parameters from mechanical images.
Walrasian Price Equilibrium

In this chapter the focus is on general economic equilibrium problems, in particular, Walrasian price or pure exchange equilibria. This problem has been extensively studied in the economics literature dating to Walras (1874); see also Wald (1951), Debreu (1959), and Mas-Colell (1985). Specifically, in this chapter we apply the powerful theory of variational inequalities to both the qualitative analysis of general economic equilibria as well as to their computation.
Microsoft TerraServer: a spatial data warehouse

Microsoft® TerraServer stores aerial, satellite, and topographic images of the earth in a SQL database available via the Internet. It is the world's largest online atlas, combining eight terabytes of image data from the United States Geological Survey (USGS) and SPIN-2. Internet browsers provide intuitive spatial and text interfaces to the data. Users need no special hardware, software, or knowledge to locate and browse imagery. This paper describes how terabytes of “Internet unfriendly” geo-spatial images were scrubbed and edited into hundreds of millions of “Internet friendly” image tiles and loaded into a SQL data warehouse. All meta-data and imagery are stored in the SQL database.TerraServer demonstrates that general-purpose relational database technology can manage large scale image repositories, and shows that web browsers can be a good geo-spatial image presentation system.
M/RMS: an EMG method for quantifying upper motoneuron and functional weakness.

A new method for quantifying upper motoneuron (UMN) weakness using standard EMG equipment is presented and compared to the twitch occlusion method. Control subjects and patients with stroke, spinal cord injury (SCI), and peripheral nerve injury (PNI) were evaluated. Force, EMG, and twitch force from nerve electrical stimulation were recorded during isometric contractions of the biceps and triceps. Ratios of the elicited CMAP amplitude (M)/voluntary-root-mean-square EMG activity (RMS) and of the voluntary contraction twitch force (Ti)/the resting twitch force (Tmax) were the two measures of UMN weakness studied. Both ratios are linearly correlated with force for controls, log M/RMS (r = 0.96) and Ti/Tmax (r = 0.86). Log M/RMS ratio was abnormally high (> mean + 2 SD; i.e., > 1.09) for weak muscles affected by stroke and incomplete SCI, but was normal in muscles weakened by PNI. An elevated M/RMS ratio, may aid in quantification of deficient supraspinal activation from UMN or functional weakness.
Detecting oxide quality problems using JT testing

The author demonstrates that JT testing is much more effective in detecting subtle defect problems on advanced thin gate technologies than the traditional ramped voltage tests. A comparison of the traditional ramp voltage tests and JT tests has been made relative to detecting subtle oxide defect problems. It has been found that, due to electron trapping, some types of gate oxide problems cannot be detected by using the JEDEC ramp voltage test, but, they can easily be detected by using the JEDEC JT test. A discussion of why this occurs along with several examples of different gate oxide problems is presented. >
Differential Reduction of CO2 by Molybdenum and Vanadium Nitrogenases

The molybdenum and vanadium nitrogenases are two homologous enzymes with distinct structural and catalytic features. Previously, it was demonstrated that the V nitrogenase was nearly 700 times more active than its Mo counterpart in reducing CO to hydrocarbons. Herein, a similar discrepancy between the two nitrogenases in the reduction of CO2 is reported, with the V nitrogenase being capable of reducing CO2 to CO, CD4, C2D4, and C2D6, and its Mo counterpart only capable of reducing CO2 to CO. Furthermore, it is shown that the V nitrogenase may direct the formation of CD4 in part via CO2-derived CO, but that it does not catalyze the formation of C2D4 and C2D6 along this route. The exciting observation of a V nitrogenase-catalyzed CC coupling with CO2 as the origin of the building blocks adds another interesting reaction to the catalytic repertoire of this unique enzyme system. The differential activities of the V and Mo nitrogenases in CO2 reduction provide an important framework for systematic investigations of this reaction in the future.
Limitations of the symptom-oriented approach to psychiatric research

BACKGROUND We critically reviewed the arguments of the symptom-oriented researchers who propose to replace syndromes and diagnostic categories with symptoms as units of analysis in psychiatric research. METHOD Three central arguments were examined: (a) current diagnostic categories lack reliability and validity; (b) using diagnostic categories leads to misclassification and confounding; and (c) symptom-oriented theories are clearer, easier to test, and more likely to lead to an explanation of psychopathology. These arguments are based on three assumptions respectively: (a) symptoms have higher reliability and validity; (b) underlying pathological processes are symptom-specific; and (c) elucidation of the process of symptom development will lead to (and must precede) the discovery of the causes of syndromes. RESULTS We found little evidence supporting these assumptions and arguments based on them. CONCLUSION There are no clear advantages in replacing syndromes with symptoms as units of analysis for psychiatric research.
A Defense of Traditional Hypotheses About the Term Structure of Interestrates

Expectations theories of asset returns may be interpreted as stating either that risk premia are zero, or that they are constant through time. Under the former interpretation, different versions of the expectations theory of the term structure are inconsistent with one another, but I show that this does not necessarily carry over to the constant risk premium interpretation of the theory. Furthermore, I argue that differences among expectations theories are of 'second order" in a precise mathematical sense. I present an approximate linearized framework for analysis of the term structure in which these differences disappear, and I test its accuracy in practice using data from the CRSP government bond tapes.
Mutation of Java objects

Fault insertion based techniques have been used for measuring test adequacy and testability of programs. Mutation analysis inserts faults into a program with the goal of creating mutation-adequate test sets that distinguish the mutant from the original program. Software testability is measured by calculating the probability that a program will fail on the next test input coming from a predefined input distribution, given that the software includes a fault. Inserted faults must represent plausible errors. It is relatively easy to apply standard transformations to mutate scalar values such as integers, floats, and character data, because their semantics are well understood. Mutating objects that are instances of user defined types is more difficult. There is no obvious way to modify such objects in a manner consistent with realistic faults, without writing custom mutation methods for each object class. We propose a new object mutation approach along with a set of mutation operators and support tools for inserting faults into objects that instantiate items from common Java libraries heavily used in commercial software as well as user defined classes. Preliminary evaluation of our technique shows that it should be effective for evaluating real-world software testing suites.
An algorithm for PET tumor volume and activity quantification: without specifying camera's point spread function (PSF).

Purpose: The authors have developed an algorithm for segmentation and removal of the partial volume effect (PVE) of tumors in positron emission tomography(PET)images. The algorithm accurately measures functional volume (FV) and activity concentration (AC) of tumors independent of the camera's full width half maximum (FWHM). Methods: A novel iterative histogram thresholding (HT) algorithm is developed to segment the tumors in PETimages, which have low resolution and suffer from inherent noise in the image. The algorithm is initiated by manually drawing a region of interest (ROI). The segmented tumors are subjected to the iterative deconvolution thresholding segmentation (IDTS) algorithm, where the Van-Cittert's method of deconvolution is used for correcting PVE. The IDTS algorithm is fully automated and accurately measures the FV and AC, and stops once it reaches convergence. The convergence criteria or stopping conditions are developed in such a way that the algorithm does not rely on estimating the FWHM of the point spread function (PSF) to perform the deconvolution process. The algorithm described here was tested in phantom studies, where hollow spheres (0.5–16 ml) were used to represent tumors with a homogeneous activity distribution, and an irregular shaped volume was used to represent a tumor with a heterogeneous activity distribution. The phantom studies were performed with different signal to background ratios (SBR) and with different acquisition times (1 min, 3 min, and 5 min). The parameters in the algorithm were also changed (FWHM and matrix size of the Gaussian function) to check the accuracy of the algorithm. Simulated data were also used to test the algorithm with tumors having heterogeneous activity distribution. Results: The results show that changing the size and shape of the ROI during initiation of the algorithm had no significant impact on the FV. An average FV overestimation of 30% and an average AC underestimation of 35% were observed for the smallest tumor (0.5 ml) over the entire range of noise and SBR level. The difference in average FV and AC estimations from the actual volumes were less than 5% as the tumor size increased to 16 ml. For tumors with heterogeneous activity profile, the overall volume error was less than 10%. The average overestimation of FV was less than 10% and classification error was around 11%. Conclusions: The algorithm developed herein was extensively tested and is not dependent on accurately quantifying the camera's PSF. This feature demonstrates the robustness of the algorithm and enables it to be applied on a wide range of noise and SBR within an image. The ultimate goal of the algorithm is to be able to be operated independent of the camera type used and the reconstruction algorithm deployed.
DCIV and spectral charge-pumping studies of /spl gamma/-ray and X-ray irradiated power VDMOSFET devices

This paper reports the total dose effects and post-irradiation anneal effects on the two recombination current peaks and the bottom current in commercial power VDMOSFET devices irradiated with /sup 137/Cs /spl gamma/-ray or X-ray radiation. The two interface recombination current peaks show a slightly different rate of increase as a function of the radiation dose. Slightly different diode ideality factors are found in an n-channel device, 1.70 /spl plusmn/ 0.10, 1.60 /spl plusmn/ 0.10 and 1.20 /spl plusmn/ 0.10 for the two DCIV current peaks and the bottom current, respectively. The saturation current of the gated diode, i.e., VDMOSFET, normalized by the input capacitance is shown to be a good parameter to monitor the interface state density. Spectral charge pumping data show that, of the above-midgap interface traps in an n-channel device, the energy below about E/sub i/ + 0.18 eV has a most significant increase in radiation-induced trap density and these traps may be responsible for the DCIV current peaks.
Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure and Evidence From New Hypertension Trials

The recent publication in Hypertension of the complete version of the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7) provides clinicians and scientists with a valuable resource.1 For the first time, the National Heart, Lung, and Blood Institute (NHLBI)-sponsored National High Blood Pressure Education Program Coordinating Committee presented the national blood pressure guidelines in two forms. The express version, published May 2003, was designed as a succinct guide for the busy primary care clinician.2 The complete version provides the scientific basis, rationale, extensive figures and charts, and references to support the JNC 7 recommendations. The complete version will be of value to specialists, academicians, scientists, and clinicians who seek the evidence that bolsters the report’s recommendations. There was a 6-year hiatus since JNC 6 was published, which is a much longer interval than that of previous reports. This was partially because of the anticipation of the completion of several important new clinical trials and epidemiology studies. The announcement of the formation of the writing committee for JNC 7 closely followed the publication of results of the NHLBI-sponsored Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) study.3 JNC 7 streamlined the classification of blood pressure and introduced the term “prehypertension,” which has received much attention. Prehypertension replaces the older terms of “normal” and “high normal,” which suggested complacency and that little action was needed. The term is used to encourage clinicians and patients to take this level of blood pressure more seriously. The recommendation to begin lifestyle therapy at such low blood pressures is based on strong epidemiological data indicating that the risk associated with blood pressure begins at or below these levels.1 This new concept of prehypertension is, indeed, important. However, the clear …
Differential regulation of proteoglycan 4 metabolism in cartilage by IL-1α, IGF-I, and TGF-β1

Summary Objectives To determine (1) if interleukin-1 alpha (IL-1α), insulin like growth factor I (IGF-I), and transforming growth factor-beta 1 (TGF-β1) regulate proteoglycan 4 (PRG4) metabolism in articular cartilage, in terms of chondrocytes expressing PRG4 and PRG4 bound at the articular surface, and (2) if these features of cartilage PRG4 metabolism correlate with its secretion. Methods Articular cartilage explants were harvested and cultured for 6 days with or without 10% fetal bovine serum (FBS), alone, or with the addition of 10ng/ml IL-1α, 300ng/ml IGF-I, or 10ng/ml TGF-β1. PRG4 expression by chondrocytes in the cartilage disks was assessed by immunohistochemistry (IHC). PRG4 bound to the articular surface of disks was quantified by extraction and enzyme-linked immunosorbent assay (ELISA). PRG4 secreted into culture medium was quantified by ELISA and characterized by Western Blot. Results PRG4 expression by chondrocytes near the articular surface was markedly decreased by IL-1α, stimulated by TGF-β1, and not affected by IGF-I. The level of PRG4 accumulation in the culture medium was correlated with the number of chondrocytes expressing PRG4. The amount of PRG4 bound at the articular surface was modulated by incubation in medium including FBS, but did not correlate with levels of PRG4 secretion. Conclusions Cartilage secretion of PRG4 is highly regulated by certain cytokines and growth factors, in part through alteration of the number of PRG4-secreting chondrocytes near the articular surface. The biochemical milieu may regulate the PRG4 content of synovial fluid during cartilage injury or repair.
A skin abscess model for teaching incision and drainage procedures.

Background Skin and soft tissue infections are increasingly prevalent clinical problems, and it is important for health care practitioners to be well trained in how to treat skin abscesses. A realistic model of abscess incision and drainage will allow trainees to learn and practice this basic physician procedure.
Communities of Small Mammals in Six Grass-dominated Habitats of Southeastern Oklahoma

Abstract During autumn 1991, we sampled small mammals in six grass-dominated habitats including upland ungrazed native prairie, upland improved pastures, upland mowed native prairie, upland roadside fencerows, lowland ungrazed native prairie and lowland ungrazed native prairie with forbs and shrubs in southeastern Oklahoma. Eleven species of small mammals were represented in 405 captures. Species diversity (H′) was high in upland (1.57) and lowland (1.47) ungrazed prairie and least for upland fencerows (0.86). Evenness (J′) exhibited a similar pattern and was high in upland (0.88) and lowland (0.82) ungrazed prairie and least for lowland ungrazed prairie with forbs and shrubs (0.53). Community overlap (Ro) varied from 1.00 (upland improved pastures and upland roadside fencerows) to 0.57 (upland improved pastures and upland ungrazed prairie). Abundance of small mammals was greatest in fencerows, largely due to the prevalence of hispid cotton rats (Sigmodon hispidus). Different land-use practices elicited b...
Hospital variation in rates of acid-reducing medication use after laparoscopic sleeve gastrectomy

Abstract Background Postoperative gastroesophageal reflux is one of the most important long-term complications of sleeve gastrectomy, the most common bariatric procedure. Objective To assess variation in hospital performance with laparoscopic sleeve gastrectomy using rates of acid-reducing medication use at postoperative 1 year. Setting Clinical registry of bariatric surgical patients at academic and community hospitals in Michigan. Methods We studied 2923 patients who underwent laparoscopic sleeve gastrectomy across 39 hospitals in the Michigan Bariatric Surgery Collaborative, 2007 to 2014. We compared risk- and reliability-adjusted rates of new-onset reflux—defined by new use of acid-reducing medication—across hospitals and in relation to surgical quality indicators (hospital procedure volume and 30-day complications). Results Overall, 20% of patients were newly taking acid-reducing medication at postoperative 1 year. Hospital rates of new medication use varied 3-fold, ranging from 10% (95% CI 7−15%) to 31% (95% CI 23−40%) of patients. Of the 2 hospitals with significantly lower rates of new medication use, 1 was high volume and 1 was medium volume. The 1 hospital with significantly higher rates was medium volume. Rates of acid-reducing medication use did not correlate with hospital volume or perioperative complications. Conclusion Across Michigan hospitals, rates of new acid-reducing medication use at 1 year after laparoscopic sleeve gastrectomy varied widely and did not correlate with traditional quality indicators. Future research could explore differences in surgical technique to better understand the factors underlying variation in long-term outcomes after sleeve gastrectomy.
Antibodies: Immunoconjugates and autologous cellular therapy in acute lymphoblastic leukemia

Using a case study of a 57-year-old man with relapsed/refractory precursor-B (pre-B) acute lymphoblastic leukemia (ALL), this review discusses treatment with immunoconjugates and autologous therapy in acute ALL. Three therapies--blinatumomab, inotuzumab, and CAR T cells--are considered here, each with advantages in specific clinical situations. These therapies represent some of the exciting advances that have been made in the treatment of ALL over the last several years.
Revision surgery after primary double-bundle ACL reconstruction: AAOS exhibit selection.

The scientific debate regarding whether double-bundle ACL (anterior cruciate ligament) reconstruction is superior to single-bundle ACL reconstruction continues. Although this topic has been studied extensively1-3, relatively little is known about how to perform revision surgery after a failed primary double-bundle ACL reconstruction. The addition of a second pair of tibial and femoral tunnels in double-bundle ACL reconstruction can pose technical challenges for the revision procedure. It is for this reason that double-bundle ACL reconstruction has historically been referred to as “double-bundle—double-trouble.”4 However, the current literature reveals a lack of clinical experience regarding the surgical management and outcomes of revision surgery for failed primary double-bundle ACL reconstruction. This article focuses on revision surgery after failure of a primary double-bundle ACL reconstruction procedure. The diagnostic modalities employed in the evaluation and grading of various primary femoral and tibial tunnel scenarios will be reviewed. Using current literature and the authors’ experience, representative cases and revision strategies for possible primary tunnel scenarios are discussed. Finally, a detailed surgical treatment algorithm will be proposed as a guide for surgical decision-making (Video 1 [online]). Video 1 Video demonstrating revision ACL surgery after primary double-bundle ACL reconstruction. AM = anteromedial, PL = posterolateral, AP = anteroposterior, and PA = posteroanterior. We define failure of ACL reconstruction with use of both objective and subjective parameters. Objectively, failure can be defined as a deficit of 10° of knee extension or 10° of knee flexion compared with the contralateral, uninjured side; demonstration of knee instability as assessed by the Lachman test (≥ +2), pivot-shift test (≥ +2), or arthrometer (>3 mm side-to-side difference); and/or absence of an intact graft on magnetic resonance imaging (MRI) or during arthroscopy. In addition to these strictly objective criteria, subjective outcome measures are also important. A patient presenting with pain, subtle instability, …