cssi/SciSciGPT-SciSciNet huggingface dataset:
Estimation of the functional and anatomic extent of myocardial infarction using magnetic resonance imaging

Abstract This study assesses magnetic resonance (MR) imaging for the evaluation of both the functional and anatomic extent of damage to the left ventricle (LV) from myocardial infarction (MI). This was accomplished by blinded region-of-interest analysis of 36 MR examinations (orthogonal-transaxial, electrocardiographically-gated, multiphasic, single spin-echo) for determination of ejection fraction (EF) and relative MI volume (i.e., percent of total LV myocardial volume). Comparison of the results was then made with a measure of global residual LV function (i.e., score quotient or SQ) derived from segmental scoring of LV wall motion on a two-dimensional echocardiogram (Echo) and with an EF value from a left ventriculogram (LVG), both performed relatively concurrently with MR. Significant ( p r = 0.56) and LVG-EF ( r = 0.78), and these relationships were relatively stronger when MI was located in the right coronary artery (RCA) than when it was found in the left anterior descending (LAD) distribution (e.g., MR-EF compared with LVG-EF: r = 0.87, p r = 0.48, p = NS for LAD). The best expression of relative MI volume appeared to be based upon absolute volume of regionally-thinned LV wall multiplied by a correction factor for its residual contractility and then the addition of a volume correcting for the amount of regional wall thinning by necrosis (i.e., "total-Fxn" MI volume). The overall correlations between "total-Fxn" MI volume and both Echo-SQ ( r = 0.73) and LVG-EF ( r = 0.86) were significant ( p r = 0.64, p r = 0.93, p r = 0.02, p = NS, and r = 0.47, p = NS, respectively). Regional differences in the results are probably at least partially related to limitations with orthogonal-transaxial imaging. For the evaluation of both functional and anatomic extent of MI, MR imaging (transaxial, multiphasic) is valuable, but its relative value varies between regions of the LV.
Behavior of Deep Convective Clouds in the Tropical Pacific Deduced from ISCCP Radiances

The characteristic features, the diurnal cycle, and the spatial distribution of deep convection over the equatorial Pacific and the relationship of deep convection to SST and surface-wind convergence were examined using a combined visible-IR (VS-IR) threshold method and an IR-only threshold method for diagnosing deep convection clouds (DCCs). Results suggest that deep convection is latitudinally confined to a much smaller spatial scale than that suggested by maps of outgoing long-wave radiation. The results suggested that there are two types of relationships between deep convection, SST, and surface-wind convergence: the west Pacific type and the east Pacific type. The latter relationship is observed in the east Pacific only when SST is not abnormally warm.
Effect of dietary protein status on urea metabolism and hepatic arginase activity of the pig

Abstract Experiments were conducted with cross-bred pigs to determine the effect of dietary protein concentration on liver arginase activity. In Exp. 1, pigs were fed diets containing 12, 18 or 24% protein. In Exp. 2, pigs were fed diets containing 12 or 24% protein. Pigs used in Exp. 1 were slaughtered after reaching a wt of 50 kg and after reaching 30, 60 and 90 kg wt in Exp. 2. Aliquots of a 50,000 x g liver supernatant were used for determination of arginase activity as well as endogenous activation kinetics. In addition, aliquots of the supernatants were fractionated by gel chromatography to determine the molecular species of swine liver arginase. Hepatic arginase activity was similar in pigs fed diets containing either 12 or 18% protein but greater in pigs fed the 24% protein diet. The data also indicate that greater than 70% of the hypatic cytosolic manganese is associated with arginase and that arginase activation may be regulated by manganese.
Video-Assisted Endoscopy for Congenital Heart Repair

Endoscopic imaging techniques can be used to enhance visualization of and access to remote intracardiac structures to improve congenital heart repairs. Database storage of these images builds a foundation for retrospective analysis of surgical failures and clinical correlations with other imaging techniques. The images also function as an educational tool for patients, families, and the cardiac team. Combining cardiac endoscopic imaging with interventional catheterization techniques has created a group of hybrid procedures, extending the capabilities of both the surgeon and the interventional cardiologist. This synergy has the potential to decrease therapeutic trauma.
A 26-Year-Old Woman Seeking an Abortion

DR DALEY: MS B IS A 26-YEAR-OLD STUDENT AND PART-TIME worker seeking to terminate a pregnancy. She lives near Boston with her parents. Her health insurance is through public assistance inMassachusetts.Shereceivesherprimarycare from Dr K, a house officer at Beth Israel Deaconess Medical Center. The patient is a primigravida who has been sexually active in a monogamous relationship for the past 6 years. After she and her partner received counseling about the use and efficacy of various forms of contraception, they chose to use the rhythm method. Her last menstrual period was March 24, 1999. On May 6, she sought medical attention after her period was late and a home pregnancy test result was positive. She noted breast tenderness and generalized fatigue. Citing cultural and family prohibitions to having a child while unmarried, she asked for counseling and a referral for an abortion. She also noted that she is currently attending college part-time and working part-time and is concerned about her financial and emotional capacity to care for an infant in the way she envisages the future. She notes that she has discussed this at some length with her partner, who is in full agreement. Medical history reveals gastric bypass surgery for morbid obesity, allergy-induced asthma, and trauma after a motor vehicle injury. Current medications include nonsteroidal anti-inflammatory agents for dysmenorrhea and “herbs” for weight loss. She does not smoke, drink alcohol, or use illicit drugs. Physical examination reveals a moderately obese woman in no acute distress. Vital signs were normal and general physical examination findings were unremarkable. Pelvic examination was also normal. Pregnancy test result was positive.
1,3-Sulfur Shifts: Mechanism and Synthetic Utility

While allylic migrations are well known, 1,3-sulfur shifts are relatively rare. These shifts occur through a variety of mechanisms depending upon the substrate type and the reaction conditions. Radical-chain, ion-pair, dipolar, and symmetry-forbidden 1,3-sigmatropic mechanisms have all been proposed. Allylic sulfur shifts have been used in the synthesis of sulfides and sulfones of higher complexity, the stereospecific synthesis of alkenes, and the construction of ketones. This comprehensive survey of 1,3-sulfur migrations pays particular attention to the reported mechanisms and synthetic application.
Effects of Individual Development Accounts (IDAs) on Household Wealth and Saving Taste

This study examines effects of individual development accounts (IDAs) on household wealth of low-income participants. Methods: This study uses longitudinal survey data from the American Dream Demonstration (ADD) involving experimental design (treatment group = 537, control group = 566). Results: Results from quantile regression analysis indicate that IDA participants had more household financial assets, controlling for household saving taste and other demographic variables. Program participants did not reshuffle existing assets into IDAs and IDA savings was new household wealth. Low-wealth participants benefited more from the program than those with relatively more wealth. In addition, program participation changed participants’ saving behaviors and improved household saving taste. Conclusions: IDAs facilitate asset accumulation among low-income households. Implications for social work practice are discussed.
Purification of erythropoietin by ion-exchange chromatography.

Abstract : A method is given for the purification of erythropoietin from the filtrate of acidified, boiled plasma prepared from phenylhydrazine anemic rabbits utilizing, DEAE-cellulose ion-exchange columns. The active erythropoietic factor thus prepared has been partially characterized and shown to be an acidic glycoprotein of low molecular weight.
Solid-phase synthesis of unnatural amino acids using unactivated alkyl halides

Abstract Conditions were developed for the efficient alkylation of the resin-bound benzophenone imine of glycine with a variety of unreactive alkyl halides. Alkylations were accomplished at room temperature in NMP using the phosphazene-type base, BEMP.
Fluctuations in the Earth's rotation and the topography of the core-mantle interface

As arguments in favour of the notion that very slow convection in the highly viscous mantle is confined to the upper 700 km gradually weakened over the past 20 years, so geophysicists have increased their willingness to entertain the idea that significant horizontal variations in temperature and other structural parameters occur at all levels in the lower mantle. Concomitant density variations, including those caused by distortions in the shape of the core-mantle interface, would contribute substantially to long-wavelength features of the Earth’s gravity held and also affect seismic travel times. The implied departures from axial symmetry in the thermal and mechanical boundary conditions thus imposed by deep mantle convection on the underlying low-viscosity liquid metallic core would affect not only spatial variations in the long-wavelength features of the main geomagnetic held (which is generated by dynamo action involving comparatively rapid chaotic magnetohydrodynamic how in the core) but also temporal variations on all relevant timescales, from decades and centuries characteristic of the geomagnetic secular variation to tens of millions of years characteristic of changes in the frequency of polarity reversals. Core motions should influence the rotation of the ‘solid’ Earth (mantle, crust and cryosphere), and in the absence of any quantitatively reasonable alternative line of attack, geophysicists have long supposed that irregular ‘decade’ fluctuations in the length of the day of about 5 x 10 -3 s must be manifestations of angular momentum exchange between the core and mantle produced by time-varying torques at the core-mantle interface. The stresses responsible for these torques comprise ( a ) tangential stresses produced by viscous forces in the thin Ekman-Hartmann boundary layer just below the interface and also by Lorentz forces associated with the interaction of electric currents in the weakly conducting lower mantle with the magnetic held there, and (b) normal stresses produced largely by dynamical pressure forces acting on irregular interface topography (i.e. departures in shape from axial symmetry). The hypothesis that topographic stresses might provide the main contribution to the torque was introduced by the author in the 1960s and the present paper gives details of his recently proposed method for using Earth rotation and other geophysical data in a new test of the hypothesis. The method provides a scheme for investigating the consistency of the hypothesis with various combinations of ‘models’ of ( a ) motions in the outer reaches of the core based on geomagnetic secular variation data, and ( b ) core-mantle interface topography based on gravity and seismic data, thereby elucidating the validity of underlying assumptions about the dynamics and structure of the Earth’s deep interior upon which the various ‘models’ are based. The scheme is now being applied in a complementary study carried out in collaboration with R. W. Clayton, B. H. Hager, M. A. Spieth and C. V. Voorhies.
The clinical effectiveness of stannous hexafluorozirconate as an anticariogenic agent

A new compound, stannous hexafluorozirconate, is an effective antisoluble and anticariogenic agent. This paper summarizes the initial human dental caries studies that were conducted with this agent.
Papago Indian Modernization: A Community Scale for Health Research.

Recent research in epidemiology has focused upon the relationship between rapid culture change and the health status of the participants. Many studies disclose that these transitional individuals suffer deleterious effects which can be attributed to the stresses generated by modification of their environment.Inquiry into the health consequences of culture change requires an instrument which will permit us to discern the level of modernization achieved by a particular community within a transitional social system. The present study describes the development and testing of such an instrument among the Papago Indians of southern Arizona, a tribe representing the entire spectrum of modernization phenomena from subsistence villages to urban enclaves.With the assistance of eight judges, 51 Papago Indian communities were scaled according to degree of modernization. The ratings obtained were subjected to several reliability tests and validated against conventional criteria of modernization: occupational structure...
An Improved Particle Identifier for Studies of Low-Yield Nuclear Reactions

Studies of low-yield nuclear reactions such as (He3, He6) or (He4, He8) require definite identification of about one interesting particle in the presence of 106 to 107 reaction product particles. Conventional ?E-E identifier systems are of limited value in these experiments as a small fraction of the abundant reaction particles produce ?E signals which deviate considerably from their normal value. The resulting false identification signals cause a general background in the identifier output spectrum which interferes with the peak due to interesting particles. In the improved identifier two ?E detectors are employed; each time a particle passes through the counter telescope two identifications are made, each using one of the ?E signals. If they do not agree with each other within prescribed limits (due to one of the ?E signals deviating from normal) the event is completely rejected. Fast coincidence and pile-up rejector techniques are used to reduce the effects of chance coincidences between unrelated detector signals and a fourth counter is used to reject high energy particles which pass completely through the telescope. Details of the instrument and its performance in several experiments are given, and the general problems in this type of work are also discussed.
Finite element methods for quantum electrodynamics using a Helmholtz decomposition of the gauge field

The Dirac equation of quantum electrodynamics (QED) describes the interaction between electrons and photons. Large-scale numerical simulations of the theory require repeated solution of the twodimensional Dirac equation, a system of two first-order partial differential equations coupled to a background U(1) gauge field. Traditional discretizations of this system are sparse and highly structured, but contain random complex entries introduced by the background field. For even mildly disordered gauge fields, the near kernel components of the system are highly oscillatory, rendering standard multilevel methods ineffective. We consider an alternate formulation of the governing equations obtained by a transformation of the continuum operator that decouples the system into separate scalar diffusion-like equations. We discretize the transformed system using least-squares finite elements and use adaptive smoothed aggregation multigrid (αSA) to solve the resulting linear system. We present numerical results and discuss implications of the transformed formulation in terms of the physical theory. Copyright c © 2009 John Wiley & Sons, Ltd.
Standards for medical devices in MRI: Present and future

The purpose of this review is to define the current standards addressing safety of medical devices in MRI and to describe ongoing standards development efforts. The American Society for Testing and Materials (ASTM International) began developing standard test methods for determining the MR safety of medical devices in MRI in 1997. To date, five ASTM standards addressing testing and marking medical devices and other items for use in the MR environment have been published. International Standards Organization (ISO) 14630, the general requirements standard for nonactive surgical implants, is currently being revised to include information about MR safety of passive implants and to reference the ASTM standards. To address the unique safety issues of active implants, and in particular, active implants with leads, like pacemakers and neurostimulators, a joint working group between ISO TC150/SC6 on active implants and International Electrotechnical Commission (IEC) SC 62B MT40 on magnetic resonance equipment for medical diagnosis is working to develop a technical specification for active implantable medical devices (AIMDs) in MRI. While much progress has been made, work still needs to continue to develop a complete body of test methods to allow the evaluation of the safety of medical devices in the MR environment.
Life events and psychopathology severity: comparisons between psychiatric outpatients and inpatients.

Relationships between life events stress variables and seven indices of psychopathology severity for a group of 97 never-hospitalized outpatients were compared with those of a previously studied group of 217 first-admission functional disorder psychiatric inpatients from the same geographical catchment areas. The hypotheses tested were that degree of life events stress would be correlated positively with indices of psychopathological severity and that the magnitudes of association would be higher for the outpatients. Bivariate correlations and stepwise multiple regression with other potential demographic and prognostic moderator variables provided evidence for significant, but somewhat differing, patterns in outpatient vs. inpatient stress/pathology relationships. Contrary to prediction, the magnitudes of significant and near-significant associations between life events and pathology severity were not different in the two samples. Language: en
Left-right asymmetry and the chick embryo.

Abstract Left–right (LR) asymmetry provides a fascinating example of the patterning of a major body axis during embryonic development. The chick embryo was the first system in which a molecular basis for left–right patterning was characterized, revealing that molecules known to play a role in other aspects of embryogenesis likewise are involved in the establishment of left–right asymmetry. The chick has been instrumental in the identification of a pathway of genes which regulate the sidedness of major body organs, as well as providing a basis for understanding laterality disturbances in twins. This review summarizes the advances in LR asymmetry which have been made in the chick system within the context of laterality research in general.
The Effect of Different Metal Cation Binding on the Proton Pumping in Bacteriorhodopsin

The first section of this paper is a detailed summary of studies made by us and others on metal cations binding to deionized bacteriorhodopsin (dIbR) and its variants. Our studies include the luminescence experiments of Eu3+ binding to dIbR and potentiometric studies of Ca2+ binding to dIbR, to deionized bR mutants, to bacterioopsin, and to dIbR with its C-terminus removed. The results suggest the presence of two classes of binding sites, one class has two high-affinity constants, and one has one low-affinity constant. For Ca2+ binding, there is one metal cation in each of the two high-affinity sites which are coupled to the charged aspartates 85 and 212 (known to be in the retinal cavity) but not coupled to each other. The low-affinity class can accommodate 0–6 Ca2+ ions and most of them are bound to the surface. Mg2+ has a slightly smaller value for its binding constant to the highest-affinity site. Thus, one expects more Ca2+ than Mg2+ bound to the two high-affinity sites. In the second section, we summarize our recent study on the effect of metal cation charge density (Ca2+, Mg2+, Eu3+, Tb3+, Ho3+, Dy3+) on the kinetics of both Schiff base deprotonation and proton transport to the extracellular surface. For all metal cations, the apparent rate constant of the slow components of the deprotonation process is the same as that for the transport process at 22 °C. The temperature studies, however, show this apparent equality to be fortuitous and to result from cancellation of the contribution of the energy and entropy of activation. Thus, while the entropy of activation is positive for the deprotonation process, it is negative for the proton transport process. These kinetic parameters depend weakly on the charge density, but in an opposite sense for the two processes. These results suggest that the deprotonation is not the rate-limiting step for the proton transport process. A possible mechanism is proposed in which a hydrated metal cation is used to induce the deprotonation of the protonated Schiff base and to dissociate one of its H2O molecules to donate the proton in the L M process.
Changes in Health Care Ideology In Relation to Self-Care by Families

Health care is shifting from a professional-independent to a business-bureaucratic orientation. Both professional and business ideology have been unfavorable to the development of self-care and a strong health care role for families. But business ideology contains more loopholes for the emergence of a higher level of family self-care activity. The shift forces consumers to take a cautious posture in the marketplace, encouraging active management of their own health care. Hoivever, families will obtain government support for their self-care activities and a policy-influential role in health system governance only through organized political action.
Exciton tunneling in wide-band-gap semiconductors

We have studied exciton tunneling in (Zn,Cd)Se/ZnSe asymmetric double quantum wells using femtosecond time resolved transmission, photoluminescence and time-resolved photoluminescence measurements. The strong Coulomb correlation as well as Frohlich electron LO-phonon interaction in II-VI semiconductors make the tunneling process significantly different from that in III-VI structures. We observe fast (1 ps) exciton tunneling out of the narrow well, although LO-phonon scattering is forbidden for holes in a single- particle picture. However, our theoretical analysis shows that tunneling of the exciton as a whole entity with the emission of only one LO-phonon is very slow. Instead, the exciton tunnels via an indirect state in a two-step process whose efficiency is dramatically enhanced by Coulomb effects.
The spatial variation of the quasi-Fermi potentials in p-n junctions

Approximate analytical solutions are obtained for symmetrical p-n junctions which provide the range of bias for constant quasi-Fermi potentials across the transition region under forward bias and small reverse bias. The solutions also show that the variations of the quasi-Fermi potentials are essentially complete in the transition region for large reverse bias. The actual spatial dependences are computed numerically for the step junction case, using the parabolic potential as first approximation and applied junction voltage as the parameter, and are graphed. Numerical calculations and curves are also made in this case for the total change of the quasi-Fermi potentials across the transition region as a function of bias voltage, with the barrier height as a parameter. These confirm the commonly adopted assumption that the quasi-Fermi potentials are essentially constant across the transition region for small bias.
Numerical scheme approximating solution and parameters in a beam equation

We present a mathematical model which describes vibration in a metallic beam about its equilibrium position. This model takes the form of a nonlinear second-order (in time) and fourth-order (in space) partial differential equation with boundary and initial conditions. A finite-element Galerkin approximation scheme is used to estimate model solution. Infinite-dimensional model parameters are then estimated numerically using an inverse method procedure which involves the minimization of a least-squares cost functional. Numerical results are presented and future work to be done is discussed.
Health Locus of Control Beliefs and Healthy Survival with AIDS

Background Health Locus of Control (HLOC) has been related to a number of psychosocial and medical variables in previous research in HIV. However, there is little information about its relationship to disease status, or about the Doctors subscale (DHLOC), in this population.
Using Representations, Decomposition, and Approximations of Practices to Support Prospective Elementary Mathematics Teachers' Practice of Organizing Discussions.

This paper examines a series of instructional activities that provide prospective elementary teachers with an opportunity to engage in one of the more difficult practices to learn within mathematics teaching—organizing a mathematical discussion. Within a mathematics methods course, representations and decomposition of practice built from the Five Practices framework (Smith and Stein in Five practices for orchestrating productive mathematics discussions. Corwin Press, Thousand Oaks, CA, 2011) were implemented and studied to examine how prospective elementary teachers set goals, selected and sequenced available student work, and planned questions within a mathematical discussion. We examined prospective elementary teachers’ strengths and weaknesses in these facets through an approximation of practice set in a lesson context familiar to the prospective elementary teachers. Our results demonstrated that although prospective elementary teachers set varying goals for a discussion, their pedagogical choices in planning their discussion tended to be consistent with the goals they have set. These results support the focused development of prospective elementary teachers’ goal setting as an implication for mathematics teacher educators.
Device considerations for development of conductance-based biosensors

Design and fabrication of electronic biosensors based on field-effect-transistor (FET) devices require understanding of interactions between semiconductor surfaces and organic biomolecules. From this perspective, we review practical considerations for electronic biosensors with emphasis on molecular passivation effects on FET device characteristics upon immobilization of organic molecules and an electrostatic model for FET-based biosensors.
Comparative tests of multimodal traffic equilibrium methods

Abstract In this study we proceeded to test the relative efficiencies of the two main computational techniques now available for calculating the traffic equilibrium in multimodal networks, namely, the relaxation and projection methods. Since both of these methods solve at each step a mathematical programming problem, we first set out to test the Frank-Wolfe algorithm and the Dafermos-Sparrow algorithm and found the latter to be the more efficient algorithm. As expected, this was also the case when these algorithms were used to solve the mathematical programming problem at each step of the relaxation method. We then investigated how different versions of the projection method enhance its performance. Subsequently, we proceeded to our main goal to compare the best projection method with the relaxation method. We tested multimodal networks with three different classes of monotone travel cost functions and found that the form of the travel cost functions affects the performance of the two basic techniques available for computing the multimodal equilibrium.
Diagenetic trends in the siliceous facies of the Monterey Shale in the Santa Maria region, California

X-ray diffraction and oxygen isotopic analyses of outcrop and subsurface samples of siliceous rocks were used to reconstruct thermal and diagenetic histories of the Miocene Monterey Shale near Santa Maria, California. Within many stratigraphic sections soft, porous diatomaceous rocks change gradationally to underlying hard and brittle chert, porcellanite, and siliceous shale; the accompanying silica mineral zones are, in descending stratigraphic order: (1) biogenic silica (opal-A), (2) cristobalitic silica (opal-CT), and (3) microcrystalline quartz. Boundaries between silica mineral zones and stratigraphic horizons are often discordant. Within the opal-CT zone, the d(101)-spacing of opal-CT decreases in a smooth non-linear fashion from about 4 10 A to 4-04 A. In the Santa Maria Valley and Bradley oil field areas the thicknesses of the opal-CT zones are greater and the present thermal gradients less than in the adjacent Orcutt oil field. Thin opal-CT zones at shallow maximum burial depths apparently correlate with higher thermal gradients. Using present thermal gradients and reconstructed maximum burial depths from well data in the Santa Maria region, the ranges in temperatures for the top and base of the opal-CT zone are 38–54 °C and 55–110 °C, respectively. The temperature difference between these two boundaries ranges from 17 to 60 °C. In comparison, temperature ranges for these two boundaries computed from oxygen isotopic compositions of opal-CT and quartz, extrapolated experimental quartz-water fractionations, and assuming δO18= 0%o for the isotopic composition of the equilibrating fluid are 18–56 °C and 31–80 °C for the top and base of the opal-CT zone, respectively. The temperature difference between these boundaries is 11–36 °C using this method. Thermal gradients and sedimentation rates strongly influence rates of silica transformations. Reconstructed thermal and diagenetic histories of siliceous rocks of the Monterey Shale at four well sites in the Santa Maria region demonstrate that most silica conversions probably occurred during the last 3–4 Myr in response to accelerated rates of sedimentation (and therefore burial heating) during the Pliocene.
Regulation of transcription of genes required for fatty acid transport and unsaturated fatty acid biosynthesis in Escherichia coli by FadR.

Summary Fatty acid biosynthesis and fatty acid degradation in Escherichiacoliare co-ordinately regulated at the level of transcription by the product of the fadRgene, FadR. In the present work we investigate FadR interaction with the fabA and fadL promoters. The FadR-responsive operator within fabA, OA, was localized to a region −47 to −31 base pairs relative to the start of transcription using DNase I protection studies. The promoter and untranslated leader within fadL had two binding sites for FadR, OL1 at −25 to −9 and OL2 at −1 to +16 relative to the start of transcription. The binding affinity of FadR for OA and OL1 or OL2 was lower than that for the single site within fadB (OB) as measured using protein-DNA gel retention assays. Overall, these experiments demonstrated that the affinity of FadR binding for DNA containing the fadB, fadL and fabA promoters was OB > OL1, OL2 > OA. We could not distinguish separate binding affinities for OL1 or OL2. We demonstrated repression of fadL transcription and activation of fabA transcription in vitro using run-off transcription assays containing purified FadR and RNA polymerase.
Novis: a visual laboratory for exploring the design of processor arrays

Abstract Novis, an experimental visual environment which supports the interactive development and animated simulation of special-purpose parallel architectures, is presented. In sharp contrast with other systems which concentrate on the representation of parallelism within programs, Novis lets users design networks at an abstract level by placing processing elements into a connected grid of arbitrary (user-selected) shape. The environment's underlying philosophy of maximal information hiding makes it unnecessary for the user to be intimately familiar with the details of low-level issues such as process schedule maintenance and event dispatching. Layout violations and exceptions detected during execution simulation (e.g. deadlock) are automatically reported to the user. An overview of Novis's features is followed by an example walk-through that imparts to the reader the feel of working in the environment. Considerations which influenced the design and implementation of the system are also discussed.
Measured and modeled effects of benthic algae on eutrophication in Indian River-Rehoboth Bay, Delaware

A combination of field studies and mathematical modeling was used to examine the role of subtidal benthic algae in the eutrophication processes in two shallow estuarine systems. Field measurements indicated uptake by benthic algae retained ammonium and phosphate in the sediments when light at the sediment surface exceeded ≈150 μE m2 s−1. The measurements were used to calibrate a newly developed model of benthic algal activity. The benthic algal model was coupled with a hydrodynamic model, a eutrophication model, and a sediment diagenesis model. In the simulated ecosystem, benthic algae had a major influence in the intra-annual cycling of nitrogen and phosphorus. When nutrients were abundant in the water column (late winter and spring) they were transferred to the sediments through algal activity. Diagenesis released these nutrients to the water column in summer when nutrients were scarce. As a result of the nutrient transfer, annual primary production in the water column, in the presence of benthic algae, exceeded production in the absence of the algae.
Brainstem neural conduction biomarkers in lead-exposed children of Andean lead-glaze workers.

Pediatric lead (Pb) intoxication remains a major medical challenge in some developing countries where Pb is used in glazing industries. Pb exposure is reported to induce neurophysiological and neurocognitive impairment in children. However, the threshold and level of Pb intoxication necessary to ind
PARS PLANA VITRECTOMY IN OCULAR TRAUMA

Visual improvement was achieved in 62% of 100 consecutive patients with ocular trauma treated by pars plana vitrectomy. Anterior segment injuries had a better prognosis than posterior segment injuries, and retinal detachment was a poor prognostic sign. Patients undergoing vitrectomy during the two weeks after injury had a better visual prognosis than those who had delayed vitrectomy. Pars plana vitrectomy has increased the recovery rate in traumatized eyes which previously were deemed inoperable and frequently were enucleated. Most such eyes have intraocular fibrocellular proliferations, resulting in traction retinal detachments, cyclitic membranes, and phthisis, as documented in clinicopathological and experimentally produced specimens of penetrating ocular trauma. Vitrectomy can interrupt this sequence, if performed one to 14 days after injury, by removing the vitreous scaffold onto which proliferation occurs, together with the elements of hemorrhage, damaged lens, vitreous, and foreign material which may incite proliferation. We believe four to ten days after injury to be the optimal time for vitrectomy to avoid the hazards of immediate intervention, while removing damaged tissue before serious sequenlae occur.
Lens Design Without A Computer

The use of an optimization program on a large computer for the design of lenses is a very recent phenomenon. Prior to about 1930 all lenses were designed by logarithms, and from 1930 to about 1960 they were designed by hand with the aid of a mechanical desk calculator and a book of sine tables. It is the purpose of this paper to indicate the kind of procedure that used to be followed when lenses were designed in this way. A numerical example is included to illustrate the process.
Supporting future surgical innovation. Lung transplantation as a case study.

OBJECTIVE: Using lung transplantation as a case study, this article addressed the problem of supporting innovative clinical surgery in an era of increasing pressures for cost containment. SUMMARY BACKGROUND DATA: After sporadic attempts at lung transplantation during the 1960s and 1970s, its clinical development began in earnest during the early 1980s. As a result of a wide range of incremental advances, the results have improved significantly. The Health Care Financing Administration, however, has not yet issued a national policy covering lung transplants and has left the coverage decision to the discretion of its regional contractors. METHODS: The authors surveyed the major commercial insurers, the Blue Cross Blue Shield Association, and a sample of Medicare intermediaries to evaluate the coverage of lung transplantation. They also interviewed the National Heart, Lung, and Blood Institute and industrial firms about their support for clinical research. RESULTS: Government and industry funding were limited, and the development and assessment of lung transplants have been financed predominantly by academic institutions through cross-subsidization from patient care and teaching funds. The major private payers and Blue Cross Blue Shield decided to cover this procedure in the early 1990s. Coverage decisions by Medicare intermediaries, however, revealed considerable variability. Moreover, the absence of a specific diagnosis-related group for lung transplants had considerable consequences for institutions in all-payer states, in which payments appeared to be considerably lower than the mean costs of a transplant procedure (about $110,000). CONCLUSIONS: This analysis indicated that there was a growing disparity between the increasing demand for outcomes data about new procedures and the limited resources available for supporting the development and assessment of new operations. It this disparity is not addressed, the rate of surgical innovation may be jeopardized, and timely outcomes data may not be acquired. It was concluded that provisional coverage within a predetermined research protocol may be a promising mechanism to remedy this situation, providing timely assessment of new procedures before widespread application.
An Examination of Preferences for Subject Matter in Painting

Two samples were used, college students and art museum attendees. Both groups were asked to rank order nine different areas of subject matter in painting in terms of personal preference. No visual examples of the suggested subject matter were provided, although brief descriptions were given when it was deemed necessary. Based on rankings, all samples and the male and female sub-samples of the student sample showed highly significant within and between groups differences. The findings are argued to be contrary to those expected by those holding a position of “relativism” with respect to art. The possibility of a dual system of aesthetics with respect to art judged for personal acquisition and abstract evaluation is discussed.
Unexpected toxicity of combined modality therapy for small cell carcinoma of the lung. A Southwest Oncology Group study.

Abstract Combination chemotherapy with cyclophosphamide, vincristine, methotrexate and Adriamycin was delivered to 35 patients with small-cell carcinoma of the lung (28 with extenstive and 7 with limited disease), including elective administration of intrathecal methotrexate. Whole-brain irradiation (3000 rad in 10 fractions) was then administered, with concomitant systemic cyclophosphamide and methotrexate for patients with extensive disease. Those with limited disease received concomitant chest irradiation without chemotherapy. Maintenance therapy then involved cyclophosphamide 750 mg/m 2 day 1, and methotrexate 30 mg/m 2 days 1 and 8, every 3 weeks. In only 2 patients reinduction was carried out at 24 weeks with the original chemotherapy. Myelosuppression was severe; there were at least 2 drug-related deaths from this cause in the induction period, and 15 febrile episodes with leukopenia. Stomatitis was more frequent and more severe in "maintenance" than in "induction" courses, especially the first maintenance course which was given with concomitant whole-brain irradiation. In addition, 13 episodes of unusual toxicity occurred in close temporal relation to systemic methotrexate administration, usually associated with stomatitis, in patients who were on maintenance therapy. These included 3 episodes of loss of consciousness, 4 of generalized erythroderma, 2 of "flu"-like syndrome, and I each of the following: fatal, bilateral interstitial pneumonia; reversible, eosinophilic pleural effusion; acute myocardial infarction; and renal compromise with hematuria. As a result of this unexpected and protean toxicity, the pilot study was discontinued. However, at this time seven patients (4 with extensive and 3 with limited disease) remain in complete remission.
Clinical location of hook of hamate: A technical note for endoscopic carpal tunnel release

Endoscopic carpal tunnel release involves a limited surgical exposure to release the transverse carpal ligament* (TCL).‘** Topographic landmarks can provide valuable reference points to enhance an operation. The hook of the hamate is a useful guide to the ulnar (safe) border of the carpal canal but can be difficult to palpate. Kaplan’s cardinal line has been used to estimate the position of the hook of the hamate and the superficial palmar arch. However, the accuracy of this technique is questionable because it is based on a moving reference point, the web space of the thumb. We report a technique to localize the position of the hook of the hamate and define key relationships of clinical importance for endoscopic carpal tunnel release.
Discourse This! Designers and Alternative Critical Writing

ABSTRACTThroughout the history of design critical writing, scholars and critics have employed standard rhetorical strategies of exposition to ground their critical discourse. This essay focuses on a different group of design writers I call “designwrights.” These writers use the rhetorical position of fiction to capture facets of the design world not readily expressed in expository prose. The essay examines some historical origins and contemporary work by designwrights such as William Morris, W.A. Dwiggins, Putch Tu and Bruce Sterling—writers who invent personae and neologisms, who craft manifestoes or satire, and who have expanded the possibilities for the form and delivery of critical design writing.
Bilateral superior rectus transposition for congenital exotropia associated with anomalous medial rectus muscles

Superior rectus transposition to the lateral rectus insertion without inferior rectus transposition has been used to correct esotropic deviations secondary to Duane syndrome and abducens nerve palsy. This is usually combined with an augmented posterior fixation suture of the superior rectus muscle to the lateral rectus muscle and ipsilateral medial rectus recession. We report a child with a large-angle congenital exotropia who was found to have anomalous medial rectus muscles bilaterally. Bilateral superior rectus transposition to the medial rectus insertion with bilateral lateral rectus recessions achieved good ocular alignment in primary position.
Workplace Demands, Economic Reward, and Progression of Carotid Atherosclerosis

Background Characteristics of the work environment have been associated with cardiovascular morbidity and mortality, but it is unclear whether these factors are associated with preclinical manifest...
Serological techniques for detection of citrus tristeza virus

Citrus tristeza virus (CTV) is the most economically important virus disease of citrus. In the last ten years, remarkable progress has been achieved in the development and improvement of new serological methods for CTV detection so that serology has become a dependable tool for many research, extension and regulatory purposes worldwide. CTV-specific polyclonal antisera and monoclonal antibodies have been developed in different research laboratories and used extensively in a wide range of different studies. This review describes the diverse serological methods developed for CTV detection and analyzes the advantages, disadvantages, relative sensitivity, applications, and present status of each method.
Lipid metabolism in pregnancy. II. Postheparin lipolytic activity and hypertriglyceridemia in the pregnant rat

Plasma postheparin lipolytic activity (PHLA) has been measured in rat pregnancy to qualitatively assess mechanisms of triglyceride removal from the circulation. This assessment can be made if the larger plasma volume of pregnancy is considered. A supramaximal dose of heparin avoids dilution of the heparin stimulus to PHLA release. Dilution of the released PHLA is corrected using measurements of plasma volume. In addition, no evidence of circulating inhibitors is present, and timing of PHLA appearance is unaffected by pregnancy. Prior studies of postheparin lipolytic activity in human pregnancy have not taken the effect of plasma volume into account and must therefore be reconsidered in light of the present results. We observed a biphasic pattern in PHLA over the course of gestation. Levels were increased in midgestation (day 12), declined to normal by day 19, and fell rapidly to one-half of control by day 21. Assuming a functional role for the triglyceride lipases represented in PHLA, the data suggest the following hypothesis: triglyceride removal is increased or normal for the greater part of gestation and is decreased only at term. If this hypothesis proves true, the hypertriglyceridemia of pregnancy should be due largely to overproduction, with decreased removal contributing only near term.
Extended theoretical considerations for Mass resolution in the resonance ejection mode of quadrupole Ion Trap Mass Spectrometry

Proceeding from the pseudopotential-well approximation for ion motion in a quadrupole ion trap, mathematical expressions are derived to describe the excitation amplitude of an ion packet at a given mass-to-charge ratio. Ion-neutral collisions are incorporated to describe the damping of ion trajectories and to describe the distribution of individual ion trajectories about a mean amplitude for the ion packet. The rate of increase of the amplitude during scanning is related to expressions that describe the amplitude dispersion of the ions at the time of ejection from the trap, which is operating in a resonance ejection scanning mode to describe the temporal line width of the ejected ion packet. The temporal line width is related to mass resolution under a number of different scanning conditions. Included in the discussion are considerations of the effect on resolution of the resonance excitation voltage, temperature, pressure, noise, and buffer-gas composition. An expression for the maximum possible resolution at high ion mass-to-charge ratios is developed, and these results are compared to an existing theoretical construction. The expressions derived under the pseudopotential-well approximation are further extended to high q z values and compared to experimental data previously published by two other researchers.
Experimental values of rate constants and ion product distributions for reactions of a series of ions with CS2

Abstract Rate constants and product ion distributions have been determined in a Selected Ion Flow Tube (SIFT) for the reactions of He + , He 2 + , Ar + , N 2 + , N + , CO + , CO 2 + , O + , D + , CS + , C + , S + , CS 2 + , S 2 + and D 3 + with CS 2 at 297 K. These ions have recombination energies varying from 2372 kJ/mol (24.58 eV) for He + to 903 kJ/mol (9.36 eV) for S 2 + . The reactions, except for the Ar + , S 2 + and CS 2 + reactions proceed at, or close to, the collisional rate with charge transfer (both dissociative and non-dissociative) being an important mechanism. S + is a common product and, in the case of D 3 + , exothermic proton transfer is rapid. For the slower reaction of CS 2 + , ternary association occurs. The reactions are discussed relative to the reactivity of these ions with the analogues, OCS and CO 2 .