cssi/SciSciGPT-SciSciNet huggingface dataset:
Vertical transmission of toxoplasma by human immunodeficiency virus-infected women.

Abstract OBJECTIVE: Our goal was to determine the frequency of mother-to-child transmission of Toxoplasma gondii from human immunodeficiency virus–infected mothers who are also chronically infected with T. gondii . STUDY DESIGN: One hundred thirty-eight women were entered into a prospective study of human immunodeficiency virus infection in pregnancy. The women were seen at enrollment, during the third, sixth, and eighth months of pregnancy (except those enrolled later in pregnancy or at delivery), at 2 and 6 months post partum, and at 6-month intervals thereafter through 4 years after delivery. Standardized interviews and physical examinations were performed, and blood was drawn at each visit. Toxoplasma serologic testing was performed on the sample drawn earliest in pregnancy; the Sabin-Feldman dye test for immunoglobulin G antibodies and enzyme-linked immunoassays for immunoglobulins M, A, and E were used. Univariate analysis for categoric variables was performed with χ 2 and two-tailed Fisher exact tests, and for continuous variables the Student t test was used. Statistical Analysis System procedures were followed. RESULTS: Twenty-eight of 138 (20.2%) women who had positive test results for human immunodeficiency virus had positive findings of the Sabin-Feldman dye test. Serologic status for T. gondii did not correlate with age, immune status, parity, or drug use. One of 27 children born to women who were seropositive for both human immunodeficiency virus and T. gondii (one child's serologic status for T. gondii was unknown) had Sabin-Feldman dye test antibodies beyond age 6 months (3.7%, 95% confidence interval 0.09% to 18.9%). Among the cohort of human immunodeficiency virus–infected mothers the rate of mother-to-child human immunodeficiency virus transmission did not vary with maternal Toxoplasma status. However, with sample sizes of 28 and 110, respectively, for the mothers who were T. gondii seropositive and seronegative, the power to detect a difference in the human immunodeficiency virus transmission rate between these groups would be relatively small. CONCLUSIONS: Transmission of T. gondii from a chronically infected mother can occur in the setting of a human immunodeficiency virus infection, but this is not a common phenomenon. In a small cohort of human immunodeficiency virus–infected women we did not observe its occurrence among those without severe immunocompromise.(Am J Obstet Gynecol 1997;167:555-9.)
Immune responses in vitro. I. Culture conditions for antibody synthesis.

Abstract The addition of mercaptoethanol to the culture medium and the optimization of other components has substantially improved the response of mouse spleen cells to in vitro immunization with heterologous RBC. As a result of these changes in the medium, the necessity of rocking and feeding cultures has been eliminated. The in vitro response of C 57 Bl spleen cells was as much as 30 times greater than that achieved in vivo . This suggests the loss of an in vivo control mechanism. Because the magnitude of responses was strain dependent, this culture system may facilitate the study of the genetic control of antibody synthesis.
Steric structure activity relationships of various adrenergic agonists: ocular and systemic effects

Dextrorotatory (d) forms of adrenergic drugs are known to be much less active than the levo (Z) forms in effecting classical adrenergically mediated responses (α, β1, β2) in metabolic organs and cardiovascular tissues. Adrenoceptor intrinsic activity and affinity, enzymatic inactivation and neuronal uptake are all known to be relatively selective for the Z-forms. It is known, however, that the d-isomers of certain agonists, such as isoproterenol, are as effective or even more effective ocular hypotensive agents than their respective Z-forms or the racemates (dl) in rabbits.We tested the d- and L-isomers of epinephrine (α, β1, β2), norepinephrine (α, β1), phenylephrine (α1), isoproterenol (β1, β2) and soterenol (α, β2) for their comparative effects after topical administration on intraocular pressure (IOP), pupil diameter (PD), arterial blood pressure (ABP) (after both topical and i.v. administration), aqueous cAMP, and aqueous and plasma lactate and glucose in the normotensive rabbit model.The results wit...
Aqueous Lithium Bromide TES and R-123 Chiller in Series

This paper presents an analysis of a cold thermal energy storage (TES) system operating in series with an R-123 chiller. A lithium bromide/water (LiBr/H 2 O) solution is used both as a refrigerant and as a cold thermal storage material. The refrigerant, liquid water, is extracted from the LiBr/H 2 O strong solution during the off-peak period. The liquid water and LiBr/H 2 O weak solution, a byproduct of the refrigerant recovery process, are used during the on-peak period to cool the building. Building waste heat is pumped by the R-123 compressor to a higher temperature during the off-peak period and is used in the generator to recover the thermal storage by reprocessing the stored solution to a higher lithium bromide concentration. The storage volumetric efficiency and system COP are determined and compared to storage systems based on water/ice and liquid water. The storage volumetric efficiency is greater than a water/ice system and far exceeds the value for a liquid water system. The proposed system, which uses an external heat pump as a source of generator heat, is also compared to another LiBr/H 2 O system that uses a self-contained internal heat pump (the compressor operates independently from the chiller and uses the liberated water refrigerant as its working fluid). The system presented here outperforms both the water/ice system and the internal heat pump LiBr/H 2 O system but is unable to match the liquid water system COP. However, it has other well-defined advantages over the liquid water system and appears to be a competitive alternative to conventional TES systems.
Pituitary Hypogonadism with Adrenal Androgen Deficiency: The Effect of Chorionic Gonadotropin on 17-Ketosteroid Excretion

PATIENTS with unusual combinations of congenital anomalies and endocrinologic disease are always of interest, especially if the disorder is of such a type as to increase our knowledge of the interaction of endocrine systems. The case presented here showed an illuminating clinical picture in this respect. More important, however, was the fact that the endocrine defect was of such a nature as to allow the test of the hypothesis that adrenal androgen production is under the control of the luteinizing hormone. Of further significance was the occurrence, during therapy with chorionic gonadotropin, of changes indicative of estrin secretion. CASE REPORT A 19-year-old colored female was admitted to the Surgical Service of Georgetown University Hospital for removal of a rectal polyp. Because of apparent hypogenitalism she was transferred to the Medical Service for further study. Past history: Birth by spontaneous delivery was said to have been uneventful, and early development was normal. During childhood the pati...
Legend naturalism and scientific progress: An essay on Philip Kitcher's

Abstract Philip Kitcher's The Advancement of Science sets out, programmatically, a new naturalistic view of science as a process of building consensus practices. Detailed historical case studies—centrally, the Darwinian revolutio—are intended to support this view. I argue that Kitcher's expositions in fact support a more conservative view, that I dub ‘Legend Naturalism’. Using four historical examples which increasingly challenge Kitcher's discussions, I show that neither Legend Naturalism, nor the less conservative programmatic view, gives an adequate account of scientific progress. I argue for a naturalism that is more informed by psychology and a normative account that is both more social and less realist than the views articulated in The Advancement of Science .
TOCCATA: a customized carbon total correlation spectroscopy NMR metabolomics database.

A customized metabolomics NMR database, TOCCATA, is introduced, which uses 13C chemical shift information for the reliable identification of metabolites, their spin systems, and isomeric states. TOCCATA, whose information was derived from the BMRB and HMDB databases and the literature, currently contains 463 compounds and 801 spin systems, and it can be used through a publicly accessible web server. TOCCATA allows the identification of metabolites in the submillimolar concentration range from 13C–13C total correlation spectroscopy experiments of complex mixtures, which is demonstrated for an Escherichia coli cell lysate, a carbohydrate mixture, and an amino acid mixture, all of which were uniformly 13C-labeled.
ON FANO MANIFOLDS WITH NORMAL PROJECTIVE CONNECTIONS

In this paper, we show that a Fano manifold with a normal projective connection is necessarily a projective space. This answers a question raised by Kobayashi and Ochiai.
Bidirectional synthesis of montamine analogs

Abstract Reported herein is a bidirectional synthesis of symmetric N , N ′-diacyl hydrazide compounds closely resembling the alkaloid natural product montamine. In the process, di- tert -butyl hydrazine-1,2-dicarboxylate was smoothly dialkylated with alkyl halides, then Boc deprotected and acylated with an acetate-protected acid chloride derived from ferulic acid. After acetate removal, simple montamine analogs were obtained in excellent overall yields. Fischer indole synthesis with 4-methoxyphenylhydrazine hydrochloride and dihydrofuran provided 5-methoxytryptophol, which was then elaborated to the 1,2-bis(5-methoxyindol-3-yl)hydrazide structure bearing the substitution pattern found in montamine.
Studies of broad emission line profiles in QSOs - II. Properties of a large, predominantly radio selected sample

On donne les parametres des raies d'emission de 214 QSO. On presente une etude preliminaire des proprietes de cet echantillon
DDSE: downstream targets of the SNF3 signal transduction pathway.

Mutations in the yeast SNF3 gene affect glucose sensing and snf3 mutants show defective growth on glucose. DNA sequence dependent suppressing elements (DDSEs) are regions located in the promoters of yeast glucose transporter (HXT) genes that when present in high copy suppress the snf3 growth defect. Here we provide evidence that the multicopy DDSE suppression is due to the titration of the Rgt1p transcriptional repressor. The DDSE region from HXT4 was found to function as a UAS sequence rendering a UASgal-less LacZ gene fused to the GAL1 promoter responsive to glucose induction. Expression mediated by the UASDDSE was dependent upon the presence of Snf3p. Expression was elevated to a high level in an rgt1 mutant in the absence of Snf3p suggesting that this DDSE region contains binding sites for the Rgt1p transcriptional repressor/activator. The UASDDSE led to expression in a grr1 mutant background, which confers a defect in inactivation of Rgt1p, as predicted from the model. The presence of tandem repeats of the putative Rgt1p binding site gave results similar to those of the DDSE, suggesting that loss of repression is due to the presence of Rgt1p footprint in the multicopy DDSE.
Generalized Subharmonic Response of a Missile with Slight Configurational Asymmetries

Abstract : The quasilinear analysis of the angular motion of slightly asymmetric missiles with a cubic static moment shows the existence of nonharmonic steady- state solutions. These solutions are described by sums of three constant amplitude rotating angles. One angle rotates at the spin rate and the other two rotate in opposite directions at approximately one-third the spin rate. This generalized subharmonic motion can be very much larger than the usual harmonic trim motion and can occur for spin rates greater than eight times the resonant spin rate. The predictions of the quasilinear theory are compared with the results of exact numerical integration of the equations of motion with much better than 5% agreement in all cases.
Peanut Acclimation to Simulated Shading by Weeds

Research was conducted to assess the acclimation responses of «Florunner» peanut (Arachis hypogaea L.) to shading and the possible role of this acclimation in determining pod yield loss due to shading by weeds. The PNUTGRO model is being used to develop a model of competition for light between peanut and broadleaf weeds. This research was undertaken to validate the treatment of peanut response to shading in PNUTGRO. Peanut plants were grown in two matched growth chambers. At 2 wk after planting, light in one chamber was reduced to 51% of total daily photosynthetic photon flux density (PPFD) received by the fulllight treatment (900 μmol m −2 s −1 ). Photosynthetic rates acclimated to shading within 3 d
A Shock Tube Study of the Product Branching Ratio of the NH2+ NO Reaction at High Temperatures

The product branching ratio of NH 2 + NO → NNH + OH and NH 2 + NO → N 2 + H 2 O has been determined in the temperature range 1826-2159 K in a shock tube study. The pressure range behind reflected shock waves was 1.10 to 1.21 bar. The time history of the NH 2 radical was measured using a frequency modulation absorption technique. The initial gas mixture compositions were 8-28 ppm monomethylamine (CH 3 NH 2 ), 0.4-1.2% ammonia (NH 3 ), and 0.4% NO, and the balance Ar. According to sensitivity analysis using a detailed 125-reaction mechanism, the NH 2 profiles are mainly sensitive to the branching ratio a = k 1 a /(k 1 a + k 1 b ) under the experimental conditions of this study, and they exhibit only a small sensitivity to secondary reactions and the overall rate coefficient, k 1 = k 1 a + k 1 b . The branching ratio increases from 0.59 ′ 0.02 at 1826 K to 0.66 ′ 0.04 at 2159 K. These results are consistent with our earlier measurements of the branching ratio at lower temperature and agree with the theoretical result of Miller and Klippenstein.
In Honor of Lawrence H. Summers, Winner of the John Bates Clark Medal

L awrence Henry Summers is the 1993 recipient of the John Bates Clark Medal, an award presented by the American Economic Association every other year to an outstanding economist under the age of forty. Larry is an extraordinary research economist, as well as an active participant in economic policymaking, and to some degree a political figure. He served as a Staff Economist at the Council of Economic Advisers (1981-82), Chief Economist of the World Bank (1989-91), and is currently the Under-Secretary for International Affairs at the U.S. Treasury. This paper summarizes Larry's important research contributions.' The next four sections describe his work in the four fields of economics that were identified in the Clark Medal citation: public finance, labor economics, financial economics, and macroeconomics.2 Each section describes his substantive research contributions, and discusses novel aspects of his research strategy. The sheer quantity of Larry's published work has forced me to limit this survey to a fraction of his research, and I apologize at the outset to Larry, and his coauthors, for oversights or errors of omission. As is typical of papers of this
Limited Vocabulary Natural Language Dialogue

Subjects cooperatively solved credible, realworld problems while communicating through a computer controlled teletype system and using three different sizes of available vocabulary in a simulation of a limited vocabulary natural language computer system. Although subjects sometimes exhibited frustration with the small vocabularies, analyses of 21 dependent measures indicated that they were able to interact and solve the problems about as successfully as did their counterparts who completed the same problems with no vocabulary restrictions. The results indicate that, at least for the kinds of problems tested here, it should be possible to develop a vocabulary of limited size which is still efficient to use in the type of interactive communication that might characterize natural language computer systems of the future.
Item Banking in Computer-Based Instructional Systems

This paper examines item banking within computer- based instructional systems from both a systems and a measurement perspective. Traditionally, computer- aided instruction involves little testing, although there is a trend to incorporate posttests in the sessions. However, computer-managed instruction has incorpo rated testing since its inception. The tests employed are similar in most respects to teacher-made classroom tests. The test results are used as the basis for diagno sis, prescription, and management procedures for indi vidual or small groups of students. At the classroom level, test banking may be more appropriate than item banking. Because of the tight linkage of the tests to instructional procedures, the basic measurement issue appears to be the degree to which the approaches evolved from standardized achievement testing can be applied to the large number of short tests employed in computer-based instructional systems.
Function of song in Scott's seaside sparrow, Ammodramus maritimus peninsulae

Abstract The function of song in a Florida population of Scott's seaside sparrows was experimentally investigated during the breeding seasons of 1983–1984 by temporarily muting male birds in the field. Birds were muted by rupturing the interclavicular air sac. They remained songless for about 2 weeks but could give all of their normal calls during this time. Two rounds of mutings were administered, each preceded and followed by time budget, playback and other observations on three treatment groups: muted, shamoperated and undisturbed birds. The early muting round tested for mate and territory acquisition. These muted birds remained mateless until they regained their voices; most attracted a female after voice recovery. The early muted birds also acquired territories later than sham-operated and undisturbed birds. The mid-season muting round tested for mate and territory retention, and for changes in behaviour. All muted birds lost their mates; a few attracted new mates when they regained singing ability. Their territories either shrank or were lost, but new territories were established (or the original re-expanded) after voice recovery. The intensity of most close-range aggressive behaviour was significantly greater for muted birds than for sham-operated and undisturbed birds. There were no discernible differences between sham-operated and undisturbed birds for any attributes measured.
Rigorous determination of spontaneously dimerized ground states in 1D Heisenberg antiferromagnets

Starting from the exact result of Majumdar and Ghosh (1969) for the dimerized ground state of a Heisenberg S=1/2 antiferromagnet with competing next-nearest-neighbour interaction J2+1/2J1 on a linear chain, it is shown that this state is the ground state of the same kind of Hamiltonian, if couplings are extended up to 2n-nearest-neighbours, and the relation J1=2n, J2=2n-1, ..., J2n=1 holds. Furthermore, it is proved rigorously that this state is the ground state when n=2 and J1-2J2+J3=0, J3=2J4, in a finite interval of values of the parameter J4. A rigorous lower limit for the extension of this interval is found to be 0<or=J4<or=1/4J1. A comparison with ground-state configurations of the equivalent classical Heisenberg and Ising model is discussed.
Classifications of dynamical systems and applications in vision geometry

In this paper, we study the families of dynamical systems which can be applied to learning. We first introduce three classifications of dynamical systems, based on attractor topology, space complexity of parameter space, and information capacity. Then, we demonstrate how each class of dynamical systems can be applied to learning. Thirdly, we show that there are three different types of geometry which are related to vision, the image geometry, the information geometry, and the dynamical system geometry. Finally, we discuss the relations between vision and all three geometries. This study helps in understanding the capabilities and limitations of a family of dynamical systems. Digital image geometry has been studied for a long time. Information geometry is proposed by Amari recently which study the manifold formed by free parameters of dynamical systems and its relation to vision. Dynamical system geometry abstractly studies the behavior of dynamical systems, and this study is independent of a detailed model, like neural networks or iterated function systems. A model, like neural network, usually occupies a subspace in the space of dynamical systems. In this paper, we also explore the relations among these three geometries.
Separating Care and Cure: An Analysis of Historical and Contemporary Images of Nursing and Medicine

This paper provides a philosophical critique of professional stereotypes in medicine. In the course of this critique, we also offer a detailed analysis of the concept of care in health care. The paper first considers possible explanations for the traditional stereotype that caring is a province of nurses and women, while curing is an arena suited for physicians and men. It then dispels this stereotype and fine tunes the concept of care. A distinction between 'caring for' and 'caring about' is made, and concomitant notions of parentalism are elaborated. Finally, the paper illustrates, through the use of cases, diverse models of caring. Our discussion reveals the complexity of care and the alternative modes of caring in health care.
On the growth of infinite products of slowly varying primitive matrices

Abstract Let { A ( t )} be a sequence of bounded nonnegative matrices [each with Perron root λ( t )] satisfying a condition of uniform primitivity and having nonzero entries bounded away from 0. In a generalization of a result on powers of primitive matrices it is shown that if the matrices A ( t ) vary slowly enough (i.e., ‖ A ( t +1)− A ( t )‖⩽ e for all t and some small e), then, as soon as the entries p i,j ( t ) of the backward product A ( t ) A ( t −1), ⋯, A (1) are positive, the ratios p i , j ( t )/ p i , j ( t −1) are equal to λ ( t )+ h i , j ( t ), where for all t 0 each h i,j ( t 0 ) is small in a precisely quantified manner: the larger t 0 is and the slower the probability-normed Perron vectors V ( t ) of A ( t ) have changed in the recent past preceding t 0 , the smaller h i,j ( t 0 ) will be. (Other similar results are derived.) The resulting approximation p i , j ( t )/ p i , j ( t −1)≈ λ ( t ) is illustrated with two numerical examples.
SIV-induced activation of the blood-brain barrier requires cell-associated virus and is not restricted to endothelial cell activation.

It has never been determined if activation of the blood-brain barrier (BBB) during simian immunodeficiency virus/human immuno- deficiency virus (SIV/HIV) infection is a function of high levels of circulating virus or if the virus has to be within a cell capable of crossing the BBB to activate it. In vitro models of the BBB are becoming recognized as an acceptable method for determining the cellular events associated with HIV neuroinvasion. Cell free virus (when added in the physiologically relevant lumen) although capable of activating the endothelial cells of our in vitro BBB did not activate astrocytes beneath. SIVmac251-infected CEMx174 cells, however, were capable of activating both components of the BBB model. Here we demonstrate that an in vitro model of the BBB can be activated in a physiologically relevant manner, that SIV requires to be cell-associated and that endothelial cells of the BBB are not the only components that are activated during SIV neuroinvasion.
Synthesis of conformationally stable 1,8-diarylnaphthalenes: development of new photoluminescent sensors for ion-selective recognition.

Highly constrained 1,8-diarylnaphthalenes exhibiting stability to isomerization have been prepared utilizing two consecutive CuO-promoted Stille cross-couplings of 1,8-dibromonaphthalene and 4-alkyl-9-trimethylstannylacridines. Screening of Pd catalysts Pd(PPh(3))(4), PdCl(2)dppf, or Pd(2)(dba)(3)/t-Bu(3)P and bases such as Cy(2)NMe, t-BuOK, K(3)PO(4), and Cs(2)CO(3) in DME or DMF revealed superior results of Stille over Suzuki coupling with acridylboronic acids or pinacolate derivatives. The meso syn- and C(2)-symmetric anti-isomers of 1,8-bis(4,4'-dimethyl-9,9'-diacridyl)naphthalene, 2, and 1,8-bis(4,4'-diisopropyl-9,9'-diacridyl)naphthalene, 3, did not show any sign of syn/anti-interconversion after heating to 180 degrees C for 24 h. Using the Eyring equation, we calculated the Gibbs standard activation energy for isomerization, DeltaG degrees (), to be higher than 180 kJ/mol. PM3 calculations of 2 and 3 suggest a highly congested structure exhibiting two parallel acridyl moieties perpendicular to the naphthalene ring. UV and fluorescence spectroscopy studies of 2 and 3 revealed remarkable quantum yields of these blue and green light emitters. Fluorescence titration experiments with the syn-isomer of 2 showed highly efficient quenching by Cu(II) ions, whereas almost no quenching effects were observed with Cu(I) and Zn(II) salts. The striking difference in fluorescence quenching was attributed to significant photoinduced electron transfer, resulting in nonradiative relaxation of excited Cu(II)-syn-2. Stern-Volmer plots of syn-2 in the presence of CuCl(2) showed a sigmoidal quenching curve indicating cooperative recognition, whereas a linear response was observed with CuCl and ZnCl(2). Fluorescence experiments in the presence of various amounts of CuCl, CuBr, and Cu(ACN)(4)BF(4) proved that the quenching is cation selective and independent of the nature of counteranions.
High risk human papillomavirus at entry to prenatal care and risk of preeclampsia

Objective To determine the association between high-risk human papillomavirus (HR-HPV) and preeclampsia. Methods Retrospective cohort study of women with HR-HPV at entry to prenatal care compared with those with at least 2 normal pap smears. Preeclampsia was defined by clinical guidelines. Unadjusted and adjusted analyses were performed. Results Three hundred fourteen women with HR-HPV matched with 628 women with normal pap smears. Exposed HR-HPV patients were younger, had lower body mass index, systolic and diastolic blood pressure at entry to care, and more likely to be nulliparous and smokers. Exposed HR-HPV patients were more likely to develop preeclampsia (10.19% vs 4.94%; P = .004; adjusted odds ratio, 2.18; 95% confidence interval, 1.31–3.65). Women with HR-HPV were also more likely to deliver prematurely at less than 37 and less than 35 weeks. Conclusion HR-HPV is associated with an almost 2-fold increased risk of developing preeclampsia. This warrants a larger study, particularly when HPV infection can be prevented with vaccination.
Defining Criteria for Selective Operative Management of Pancreatic Cystic Lesions: Does Size Really Matter?

Introduction Proposed criteria for resection of pancreatic cystic lesions have included symptoms, size (>3 cm), and suspicious features by endoscopic ultrasound (EUS). The objective of this study was to evaluate risk factors for malignancy in a large series of patients undergoing resection of suspected pancreatic cystic neoplasms.
Modeling and simulating software acquisition process architectures

Abstract In this paper, we describe our efforts to support the modeling and simulation of processes associated with software system acquisition activities. Software acquisition is generally a multi-organization endeavor concerned with the funding, management, engineering, system integration, deployment and long-term support of large software systems. We first describe our approach supporting the modeling and simulation of software acquisition processes using a software process architecture (SPA). We then introduce how we support the distribution, concurrent execution and interoperation of multiple software process simulations using the high-level architecture (HLA) and run-time infrastructure (RTI) to address the complexity of software acquisition process architectures. To illustrate this, we provide examples from the design and prototyping of a Web-based environment that supports the modeling and simulation of acquisition process architectures. This environment thus serves as a new kind of software process test-bed that can demonstrate and support experiments incorporating multiple software process simulation systems that interoperate in a distributed and concurrent manner across a network.
Derivation of the Dynamics Equations of Receiver Aircraft in Aerial Refueling

This paper describes the derivation of a new set of nonlinear, 6{DOF equations of motion of a receiver aircraft undergoing an aerial refueling, including the efiect of timevarying mass and inertia properties associated with the fuel transfer and the tanker’s vortex induced wind efiect. Since the Center of Mass (CM) of the receiver is time{varying during the fuel transfer, the equations are written in a reference frame whose origin is at the CM of the receiver before fuel transfer begins and stays flxed at that position even though the CM is moving during the refueling. Due to the fact that aerial refueling simulation and control deal with the position and orientation of the receiver relative to the tanker, the equations of motion are derived in terms of the translational and rotational position and velocity with respect to the tanker. Further, the derivation of the equations takes into account the momentum transfer into the receiver due to the fuel transfer. The receiver aircraft before fuel transfer is treated as a rigid body made up of ‘n’ particles. The dynamic efiects due to fuel transfer are modeled by considering the mass change to be conflned to a flnite number of lumped masses, which would normally represent the fuel tanks on the receiver aircraft. Once the refueling begins, by using the design parameters such as the shape, size and location of the individual fuel tanks and the rate of fuel ∞owing into each of them, the mass and location of the individual lumped masses are calculated and fed into the equations of motion as exogenous inputs. The new receiver equations of motion are implemented in an integrated simulation environment with a feedback controller for receiver station-keeping as well as the full set of nonlinear, 6{DOF equations of motion of the tanker aircraft and a feedback controller to ∞y the tanker on a U-turn maneuver.
Fabrication of a hollow obturator with fluid resin

Summary Procedures for fabrication of a hollow obturator with fluid resin have been described. The construction technique is simple and accurate. It allows precise control of the thickness of the resin for minimum weight, but with sufficient thickness to allow adjustment if necessary. The technique can be used for edentulous or partially edentulous patients after maxillary resection.
Total Equivalent of Reactive Chemicals in 142 Human Food Items Is Highly Variable Within and Between Major Food Groups

Many reactive electrophilic chemicals (e.g., acrylamide and hydrazine) occur in foods, and these could individually or cumulatively contribute to human cancer or other diseases. Glutathione (GSH) reacts with and detoxifies electrophilic compounds and is used physiologically to protect against a broad range of toxic and mutagenic compounds. To elucidate the distribution of reactive chemicals in foods, we added a known amount of GSH to 142 commonly consumed food items and assayed the relative amounts of reactive chemicals in terms of the amount of GSH lost during homogenization and extraction, defined quantitatively in terms of glutathione-reactive units (GRUs). Thirty-four items contained GRUs but no detectable GSH; 53 items contained both GSH and GRUs; 18 items contained no GSH or GRUs; and 37 items contained GSH but no detectable GRUs. Among the food groups, cereals, bread, milk, and milk products had relatively high GRU concentrations and low GSH concentrations; several common beverages also had high GRU concentrations and low GSH concentrations; meats and main course dishes were generally low in GRUs and high in GSH. Fruits and vegetables varied in GRU concentration, but most fresh fruits and vegetables had considerably more GSH than GRUs; exceptions were canned vegetables, which had no GSH or GRUs; fruit drinks, which had moderate levels of GRUs and no GSH; and 3 fruits (blueberries, cherries, and prunes), which had high GRU levels. The results provide a database that can be used with food frequency analyses to evaluate the possible association of health risks with the consumption of foods high in GSH-reactive chemicals.
Site-Specific DNA Binding of the Schizosaccharomyces pombe Origin Recognition Complex Is Determined by the Orc4 Subunit

The mechanism by which origin recognition complexes (ORCs) identify replication origins was investigated using purified Orc proteins from Schizosaccharomyces pombe. Orc4p alone bound tightly and specifically to several sites within S. pombe replication origins that are genetically required for origin activity. These sites consisted of clusters of A or T residues on one strand but were devoid of either alternating A and T residues or GC-rich sequences. Addition of a complex consisting of Orc1, -2, -3, -5, and -6 proteins (ORC-5) altered neither Orc4p binding to origin DNA nor Orc4p protection of specific sequences. ORC-5 alone bound weakly and nonspecifically to DNA; strong binding required the presence of Orc4p. Under these conditions, all six subunits remained bound to chromatin isolated from each phase of the cell division cycle. These results reveal that the S. pombe ORC binds to multiple, specific sites within replication origins and that site selection, at least in vitro, is determined solely by the Orc4p subunit.
Reflections on Artful Teaching

Artfulness is an essential but often ignored element in effective teaching and learning. This article uses the art metaphor to reframe teaching as a creative, holistic learning process for both student and teacher. It challenges the traditional view of knowledge as exclusively scientific and objective and develops the idea of an equally important intuitive way of knowing. It also challenges the traditional hierarchical structure of the classroom and suggests that a collaborative web structure is much more appropriate for building a community of learners and a student-centered classroom.
First, There Was Pedagogy And Then Came Andragogy

The assertion that first, there was pedagogy and then came andragogy, is simultaneously true and misleading. What is pedagogy? What is andragogy? Which preceded the other? And what, if anything, does any of this have to do with medical education? In this article, we will explore the answers to these questions, review the historical bases for the pedagogical and andragogical paradigms, and discuss learning theories and their relevancy to teaching and learning in medicine.
Quantitative Evaluation of Cardiac Parasympathetic Activity in Normal and Diabetic Man

Heart rate and RR variation (the standard deviation of the mean RR interval for a 5-min period) were evaluated as measurements of cardiac parasympathetic nervous system activity in fasting supine diabetic (N = 22) and comparable age normal (N = 22) subjects. The rate of breathing did not effect heart rate, but was inversely related to the RR variation (r = 0.89, P less than 0.01). Heart rate was increased (P less than 0.0001) and RR variation decreased (P less than 0.05) during beta-adrenergic stimulation with isoproterenol and during parasympathetic blockade with atropine (both P less than 0.0001). Hence, the cardiac effects of beta-adrenergic stimulation may mimic the effects of diminished parasympathetic function. To evaluate parasympathetic control of RR variation, independently of possible effects of increased sympathetic activities, studies were performed during beta-adrenergic blockade with propranolol. RR variation during propranolol was less both in 14 diabetic subjects without clinical symptoms of autonomic neuropathy (P less than 0.005) and in 8 diabetics with clinical symptoms of autonomic neuropathy (P less than 0.001) when compared with 22 age-comparable normal subjects. The measurement of RR variation was very reproducible with a day-to-day coefficient of variation of 9.7 +/- 2.8% (x +/- SEM) in diabetic subjects with stable hyperglycemia. It is concluded that supine RR variation during a deep respiratory rate and during beta-adrenergic blockade is a sensitive, quantitative, and reproducible method to evaluate parasympathetic nervous activity in normal and diabetic subjects. Furthermore, cardiac parasympathetic activity may be diminished in diabetic subjects before clinical symptoms of autonomic neuropathy are evident.
Growth and acyltransferase activity of rabbit mammary gland during pregnancy and lactation.

A bimodal change in yield and microsomal pro- tein content of rabbit mammary gland was observed with the progress of pregnancy and lactation. The initial stimulus took place on day 22 of pregnancy and the second during early lactation. Palmitoyl-CoAmonopaImitoyl-sn- glycerol 3-phosphate palmitoyltransferase activity was monitored concurrently. This enzyme in rabbit mammary microsomes is composed of two isoenzymic species that differ with respect to the physical nature of the substrates with which each interacts. The activities of the two iso- enzymes were recorded at progressive stages of pregnancy, lactation, and involution to determine if a regulatory role could be assigned to either or both species. Although the patterns were indefinite, total transacylase activity did in- crease over this period, i.e., the specific activity of LPAT-a was 12 and 24 nmoles/mg protein per min in pregnancy and lactation, respectively, while that of LPAT-P rose from zero to 90 nmoles/mg protein per min over the same period. The time of harvesting in relation to the interval between nursing periods is discussed in the light of these results.
Modulation of the Hippocampal θ-Rhythm as a Mechanism for Anesthetic-Induced Amnesia

Understanding the mechanisms of anesthetic interference with memory and consciousness is of scientific value and clinical importance. For the clinician, the ability to precisely monitor the effect of anesthetics on the brain, the organ where anesthetic drugs exert their core effects (effects on all other organs, no matter how profound, are side effects), would be practice changing.
Factors shaping the development of working time regulation in the United States and Europe

. In nineteenth century Britain, the first working time regulations were prompted by humanitarian concerns about women and children employed in factories. In the United States, working time laws were initially introduced in response to union activism and labour unrest. During the twentieth century, policy-makers enacted statutes that shortened hours of work in an attempt to spread available work and thereby curb unemployment. The past 20 years, with the adoption of the European Working Time Directive, have reflected a movement towards social and political integration, continuing political pressure to curb unemployment, and growing acceptance of ergonomics and work organization as components of international safety regulation.
Computation of the circular error probability (CEP) integral

A substantial portion of the findings of J.T. Gillis (ibid., vol.27, no.6, p.906-910, Nov. 1991) were reported in the open literature nearly 45 years ago, using far simple methods. An expression for the circular error probability (CEP) which takes into account the correlation between two jointly Gaussian random variables (an aspect overlooked by Gillis) is derived and numerical results are presented. For all practical purposes, it is found that the influence of the correlation coefficient on the CEP is not particularly strong. >
N-Aralkyl-piperidyl Carbanilates as Hypocholesteremic Agents

A number of N-aralkyl-N-methylaminoethyl carbanilates have been described in the literature as possessing hypocholesteremic activity. This series of compounds now has been extended to include 12 new o-[1-(substituted benzyl)-4-piperidyl]-N-(sub-stituted phenyl) urethans and six new o-[1-(substituted benzyl)-4-piperidylideneimino]-N-(substituted phenyl) urethans. Two new derivatives of N1-[(1-substituted benzyl)-4-piperidyl]-N3(p-chloro-phenyl)urea have been prepared. Eleven intermediate piperidine derivatives, that have not been previously described in the literature, have been prepared and characterized. Fifteen of these new compounds have been studied for their ability to inhibit the incorporation of mevalonate-2-14C into cholesterol by homogenates of rat liver. Six of the compounds exhibited greater than 50% inhibition when tested at a concentration of 2 × 10−5M. Appreciable incorporation of radioactivity into 7-dehydrocholesterol was observed with these six compounds. No significant reduction in serum cholesterol levels could be found in rats dosed at a level of 40 mg./ kg. of body weight over a period of 7 days.
Byte-Oriented Error-Correcting Codes for Semiconductor Memory Systems

Byte-oriented error-correcting codes are useful in correcting and detecting errors in a memory system organized in multiple-bit-perchip fashion. This paper presents the construction of new single-byte error-correcting and double-byte error-detecting codes.
Hume’s Absolute Necessity

Hume regards the �absolute� necessity attending demonstrable propositions as an expression of the limitations of human imagination. When we register our modal commitments in ordinary descriptive language, affirming that there are such-and-such absolute necessities, possibilities, and impossibilities, we are projecting our sense of what the human mind can and cannot conceive. In some ways the account parallels Hume�s famous treatment of the necessity of causes, and in some respects it anticipates recent expressivist theories of absolute modality. I marshal the evidence for this interpretation, show how it can explain a number of otherwise puzzling features of Hume�s modal epistemology and metaphysics, and situate this account of our modal discourse in Hume�s wider programme for a science of human nature.
Neotectonics of the central Nepalese Himalaya: Constraints from geomorphology, detrital 40Ar/39Ar thermochronology, and thermal modeling

[1] The southern flanks of the central Nepalese Himalaya correspond to a sharp transition in landscape morphology and bedrock mineral cooling ages that suggests a change in rock uplift rate. This transition can be explained by either (1) accretion of footwall material to the hanging wall across a ramp in the decollement separating India from Eurasia, thereby enhancing rock uplift rates above the zone of accretion or (2) out-of-sequence surface thrust faulting at the physiographic transition. Here we use geomorphic data, 649 new detrital 40Ar/39Ar cooling ages, and a simple thermokinematic model to evaluate which of these tectonic configurations is most appropriate for the central Nepalese Himalaya. We first define and delineate the physiographic transition in central Nepal using maps of knickpoints, river steepness indices, local relief, and the distribution of thick alluvial fill deposits. We then report new detrital 40Ar/39Ar data from two trans-Himalayan transects, each of which suggests a rapid northward increase in the total amount of exhumation across the physiographic transition. Thermokinematic modeling suggests that either of the two developmental scenarios for the transition is plausible but that an accretion model is viable only under an extremely narrow range of conditions. We contend that the physiographic and thermochronologic data in our study area are most simply explained by recent out-of-sequence surface thrusting within the Lesser Himalayan metasedimentary sequence, approximately 15–30 km south of the mapped surface trace of the Main Central Thrust system. An important finding of this work is that there are substantial along-strike variations in physiography and thermal history that reflect along-strike changes in the degree and location of out-of-sequence surface thrusting.
The AAU/ARL Global Resources Program: origins and trajectory

The AAU/ARL (Association of American Universities/Association of Research Libraries) Global Resources Program was launched early in 1997 by the Association of Research Libraries, with funding from The Andrew W. Mellon Foundation. Reviews the development of the related projects that preceded the establishment of the AAU/ARL Global Resources Program, describing the context for its creation and the goals it aspires to fulfil, and identifies some of the challenges the Program faces on the path to full implementation. It is hoped that the AAU/ARL Global Resources Program will encourage us to develop true international collaboration, branching out from accomplishments thus far, as the Program itself built on the efforts that preceded it.
Quantifying causal emergence shows that macro can beat micro.

Causal interactions within complex systems can be analyzed at multiple spatial and temporal scales. For example, the brain can be analyzed at the level of neurons, neuronal groups, and areas, over tens, hundreds, or thousands of milliseconds. It is widely assumed that, once a micro level is fixed, macro levels are fixed too, a relation called supervenience. It is also assumed that, although macro descriptions may be convenient, only the micro level is causally complete, because it includes every detail, thus leaving no room for causation at the macro level. However, this assumption can only be evaluated under a proper measure of causation. Here, we use a measure [effective information (EI)] that depends on both the effectiveness of a system’s mechanisms and the size of its state space: EI is higher the more the mechanisms constrain the system’s possible past and future states. By measuring EI at micro and macro levels in simple systems whose micro mechanisms are fixed, we show that for certain causal architectures EI can peak at a macro level in space and/or time. This happens when coarse-grained macro mechanisms are more effective (more deterministic and/or less degenerate) than the underlying micro mechanisms, to an extent that overcomes the smaller state space. Thus, although the macro level supervenes upon the micro, it can supersede it causally, leading to genuine causal emergence—the gain in EI when moving from a micro to a macro level of analysis.
Pediatric eye injuries due to nonpowder guns in the United States, 2002-2012

Purpose To identify epidemiologic trends in nonpowder gun-related pediatric eye injuries and to determine factors associated with severe injury requiring hospital admission. Methods US emergency department data on pediatric eye injuries between 2002 and 2012 were reviewed using the National Electronic Injury Surveillance System. Literature review was conducted to determine trends in visual outcomes after treatment and use of eye protection. Results In 2012 roughly 3,161 children were treated in US emergency departments for nonpowder gun-related eye injuries. Since 2010 rates of severe nonpowder gun pediatric eye injury have increased by over 500% ( P = 0.039). Specifically, while rates of hospital admission due to paintball gun eye injury have dropped precipitously ( P = 0.0077), rates of admissions for air gun eye injuries have increased by over 600% since 2010 ( P = 0.033). Children sustaining eye injury due to air guns are more likely to be diagnosed and admitted with foreign body or ocular puncture injury. Roughly 28% of documented cases of airsoft or BB gun–related injury had visual acuity worse than 20/50 after initial treatment. Over 98% of injuries occurred without eye protection. Conclusions Air guns are rising in popularity and now account for the majority of pediatric eye injuries requiring hospital admissions. These eye injuries occur without ocular protection and may lead to permanent eye injury. Increasing regulations for eye protection, sales, and usage of air guns are needed to prevent serious pediatric eye injuries.