cssi/SciSciGPT-SciSciNet huggingface dataset:
cis-regulatory processing of Notch signaling input to the sea urchin glial cells missing gene during mesoderm specification

The glial cells missing regulatory gene of Strongylocentrotus purpuratus (spgcm) was proposed earlier to be the genomic target of Delta/Notch (D/N) signaling required for specification of the mesodermal precursors of pigment cells. Here, we show that microinjection of a spgcm antisense morpholino oligonucleotide results in larvae without pigment cells. Microinjection of an mRNA encoding a dominant negative form of Suppressor of Hairless (dn-Su(H)) results in reduced levels of spgcm mRNA, disruption of mesodermal founder cell specification and failure to produce pigment cells. These results confirm that this gene is required for pigment cell specification. Three cis-regulatory modules of the spgcm gene were identified, which when incorporated in a GFP expression construct recapitulate the early expression pattern of this gene. Spatial expression of this GFP expression construct is severely disrupted by co-expression of dn-Su(H) mRNA, confirming that spgcm is a direct target of canonical N signaling mediated through Su(H) inputs. cis-perturbation analysis by mutation of consensus Su(H) sites identified a conserved motif paired-site and a lone site in the middle module that function both to drive expression in SMC precursors which receive the Delta signal and to repress expression in ectopic locations which lack this signal. While these Su(H) target sites provide the cis-regulatory architecture with the core of an N signaling transcriptional response switch, both the on and off outputs from this module require additional inputs.
Factors associated with future psychiatrists' selection of academic or clinical careers.

Graduation Questionnaire data collected by the Association of American Medical Colleges (AAMC) were used to identify student and medical school characteristics associated with future psychiatrists’ career plans. Subjects were senior medical students in the class of 1986 who definitely planned to specialize in psychiatry or child psychiatry. Medical school variables such as research experience, publication history, and exposure to a research-oriented environment were associated with plans for a career in academic medicine or research (versus clinical practice). Membership in a non-underrepresented minority group, having taken elective course work at a military or government agency, and having attended a private medical school all were associated with plans for a career in salaried clinical practice (versus private clinical practice).
Linkage of loci controlling alloantigens on red blood cells and lymphocytes in the horse

A system of equine lymphocyte alloantigens designated ELA, is identified, and it is shown that the locus or loci controlling these markers must be closely linked to the locus controlling markers in the A system of horse blood groups. Among 29 offspring in two stallion families there was evidence for one recombinant. Lod scores for linkage between the A and ELA loci in the two families were 3.61 and 3.33, respectively, for theta equal to 0.
Synthesis and binding studies of neutral dioxydiamide ionophores -III

Abstract The syntheses of several bis-(1,2-phenylenedioxydiscetamides) with eight binding sites (four ethers, four amides) are described. It had been anticipated that these bis-compounds would be much stronger binders for Group IIA cations than are members of our previously described 1,2-phenylenedioxydiacetamide system, e.g. 1-3, which give isolable complexes usually of 2:1 ligand/metal cation stoichiometry. Binding constants for the new diesters 4 and 5 were determined in methanol using UV absorption changes and the Scatchard method. The binding strength of 4 was concentration dependent and only moderately greater than that for 1 or for the more closely related 4-hydroxymethyl compound 3. Diester 5 was a weaker binder for Group IIA cations than was either 1 or 3. Cooperativity of the two sets of binding sites with either Sr 2+ or Ba 2+ was demonstrated for 4 but not for 5. Electrochemical selectivity values (K pot ij) as determined by Simon et al for 4, 5, and 6, in liquid membrane electrodes are reported for various cations. High ion selectivity for Na + vs either Ca 2+ or K + were found, especially for 6.
Point Mutations in Aβ Result in the Formation of Distinct Polymorphic Aggregates in the Presence of Lipid Bilayers

A hallmark of Alzheimer's disease (AD) is the rearrangement of the β-amyloid (Aβ) peptide to a non-native conformation that promotes the formation of toxic, nanoscale aggregates. Recent studies have pointed to the role of sample preparation in creating polymorphic fibrillar species. One of many potential pathways for Aβ toxicity may be modulation of lipid membrane function on cellular surfaces. There are several mutations clustered around the central hydrophobic core of Aβ near the α-secretase cleavage site (E22G Arctic mutation, E22K Italian mutation, D23N Iowa mutation, and A21G Flemish mutation). These point mutations are associated with hereditary diseases ranging from almost pure cerebral amyloid angiopathy (CAA) to typical Alzheimer's disease pathology with plaques and tangles. We investigated how these point mutations alter Aβ aggregation in the presence of supported lipid membranes comprised of total brain lipid extract. Brain lipid extract bilayers were used as a physiologically relevant model of a neuronal cell surface. Intact lipid bilayers were exposed to predominantly monomeric preparations of Wild Type or different mutant forms of Aβ, and atomic force microscopy was used to monitor aggregate formation and morphology as well as bilayer integrity over a 12 hour period. The goal of this study was to determine how point mutations in Aβ, which alter peptide charge and hydrophobic character, influence interactions between Aβ and the lipid surface. While fibril morphology did not appear to be significantly altered when mutants were prepped similarly and incubated under free solution conditions, aggregation in the lipid membranes resulted in a variety of polymorphic aggregates in a mutation dependent manner. The mutant peptides also had a variable ability to disrupt bilayer integrity.
ADIABATIC TRANSPORT PROPERTIES AND BERRY’S PHASE IN HEISENBERG-ISING RING

In a recent paper, B. Sutherland and B.S. Shastry have constructed an adiabatic process for the Heisenberg spin chain (spin ½) with respect to a change of boundary conditions. In this paper we calculate Berry’s phase for this process. We also evaluate the dependence of energy levels on boundary conditions which permits us to calculate the effective charge-carrying mass.
Smooth estimation of multivariate survival and density functions

Abstract By considering a multivariate version of the Hille's theorem, the technique developed by Chaubey and Sen (Statist. Decisions 14 (1996) 1) is extended for estimating a multivariate survival distribution and its associated density. Asymptotic properties of the resulting estimators are investigated in detail.
Neoclassical Health Economics and the Debate over National Health Insurance: The Power of Abstraction

MARK V. PAULY, PATRICIA DANZON, PAUL J. FELDSTEIN, & JOHN HOFF, Responsible National Health Insurance. Washington, D.C.: American Enterprise Institute, 1992. Pp. 87. $22.50 (cloth); $9.75 (paper). VILLIAM A. GLASER, Health Insurance in Practice: International Variations in Financing, Benefits, and Problems. San Francisco: Jossey-Bass, 1991. Pp. 542. $70.00. It now appears that the United States will finally join the rest of the civilized world and enact some form of national universal health insurance. Early in a political debate that quickly intensified, attention crystallized around four primary candidates: first, the so-called "Canadian system" option,1 in which the federal government would completely assume the financing and price regulation of health care; second, the "playor-pay" option, in which employers would either offer their own group insurance plans ("play") or pay into a state-sponsored risk pools ("pay"), all of which would then purchase policies from competing private insurance companies; third, the "tax credit" schemes, in which our current market structure would remain largely intact, modified only by tax system
Postsynaptic bursting is essential for ‘Hebbian’ induction of associative long-term potentiation at excitatory synapses in rat hippocampus

Associative long-term potentiation (LTP) is the dominant model of memory related synaptic modifications in the mammalian brain (Bliss & Lomo, 1973; Bliss & Collingridge, 1993). It has been studied mainly in the hippocampus, a structure of importance for memory (Morris et al. 1983; Squire & Zola-Morgan, 1991). Induction of associative LTP requires activation of the N-methyl-D-aspartate (NMDA) receptor (Collingridge et al. 1983; Bliss & Collingridge, 1993), which serves as a molecular coincidence detector, requiring both presynaptic release of glutamate and postsynaptic depolarization for its activation (Nowak et al. 1984; Mayer et al. 1984). Thus associative LTP obeys Hebb's learning rule (Hebb, 1949), which suggests that when the pre- and postsynaptic elements are active at the same time then the synapse between them will be strengthened. Indeed, pairing of presynaptic and postsynaptic activity can, under some experimental conditions, lead to synaptic potentiation (Wigstrom et al. 1986; Magee & Johnston, 1997; Markram et al. 1997). However, the physiological activity that occurs during learning behaviours and which produces the critical activation of NMDA receptors, leading to synaptic potentiation in adult hippocampus, has not been determined. According to a common interpretation of Hebb's learning rule, synaptic potentiation would be expected to occur following temporal coincidence of presynaptic activity and postsynaptic single action potentials. However, when a rat learns about spatial relations during active exploration of an environment, neurons with appropriate place fields, i.e. coding for the current location of the rat in space, and therefore those neurons that are likely to be involved in associative memories, typically show bursting activity repeated at theta frequency (5-12 Hz) (e.g. O'Keefe & Recce, 1993). Perhaps postsynaptic bursts bear a special significance for associative synaptic modification. We wanted to test directly the common interpretation of Hebb's rule, by investigating whether coincident single pre- and postsynaptic action potentials are sufficient to induce LTP in hippocampal slices from adult rat. In order to investigate whether bursts have a special role in associative synaptic modification, we compared the efficacy of pairing pre- and postsynaptic single action potentials and pre- and postsynaptic bursts in inducing synaptic change using neuronal activity seen during exploratory learning.
Projectile detection using quasi-electrostatic field sensor array

Abstract Detection, localization, and ranging of the hostile fire source are very important for military and law enforcement operations. In this work authors explore use of quasi-electrostatic field created by a moving, charged projectile for the projectile detection. This paper describes development of a novel and inexpensive sensor network for detecting the quasi-electrostatic field of a charged bullet. The principle method used to sense the quasi-electrostatic field was based on a novel sensor utilizing voltage-controlled variable capacitance. A wired network was used to propagate the measurements to a central data acquisition unit. Several missile localization algorithms were explored to process the data from the sensor array making sure that all variables, including signal latency, would not affect the accuracy of the results. The results received and processed by the system report the passing objects coordinated in relation to the designated central location.
Metal complexes of modified cyclen as catalysts for hydrolytic restriction of plasmid DNA.

Abstract Simple and novel nuclease models have been synthesized. These involve metal-binding ligand 1,4,7,10-tetraazlcyclododecane (cyclen) tethered to an acridine ring (a DNA-binding group) by amide linkers of various lengths. Binding of these probes to DNA was studied by monitoring changes in their UV–visible spectra affected by the presence of DNA. Titration of these compounds with increasing amounts of pBR322 DNA caused hypochromic effects and shifted the acridine absorption at 360 nm to a longer wavelength. Under biologically relevant conditions (37 °C and pH 7.4), specific transition metal complexes of these compounds are found to be highly effective catalysts toward the hydrolysis of plasmid DNA. This is demonstrated by their ability to convert the super-coiled DNA (form I) to open-circular DNA (form II). Structure-activity correlation studies show that hydrolytic activity depends on both the structure of ligand (L 1 > L 2 > L 3 ) and the nature of metal ion cofactor (Co 3+ > Zn 2+ > Cr 2+ > Ni 2+ > Cu 2+ > Fe 3+ ).
Stable modeling in energy risk management

High price volatility in energy markets compels the companies to adopt and implement policies for measurement and management of the energy risk. A popular measure of risk exposure is the Value at Risk (VaR). Traditional methods of estimation of VaR used by major energy companies fail to capture the heavy tails and asymmetry of energy returns distributions. We suggest the use of stable distributions for modeling energy return distributions. The results of our study demonstrate that stable modeling captures asymmetry and heavy-tails of returns, and, therefore, provides more accurate estimates of energy VaR.
Third list of insects that feed upon tansy ragwort, Senecio jacobaea, in the western United States.

Five more endemic western North American insect species are reported that feed upon the introduced weed tansy ragwort, Senecio jacobaea L., in California; their known host plant spectra are given. These additional species bring the total to 42 endemic or cosmopolitan oligophagous or polyphagous insects and mites that can survive on this plant. Two of the 5 species are in the Order Hemiptera, 1 in Lepidoptera, and 2 in Diptera.
Oxidation of dithiothreitol during turnover of nitric oxide reductase: evidence for generation of nitroxyl with the enzyme from Paracoccus denitrificans.

Summary The stoichiometric relationship between thiol oxidized and NO reduced was studied for the reaction catalyzed by nitric oxide reductase from Paracoccus denitrificans . The reaction systems consisted of dithiothreitol, ascorbate, phenazine methosulfate, enzyme and NO, or that system minus ascorbate. The mole ratio of thiol groups oxidized to NO reduced was observed to be 2.3 to 1.5 over a range of NO from 0.09 to 0.35 μ mol. A ratio of 1.0 was expected for the simple reduction of NO by 1-electron to N 2 O. The oxidation of additional thiol is attributed to the trapping of nitrosyl hydride (nitroxyl, NO − /NOH) by thiol.
Cost-effectiveness of treatments for chronic hepatitis C

With increasing concern by consumers, employers, health-care payers, and policy makers, interest has grown in determining the economic efficiency of drugs. Consequently, numerous pharmacoeconomic studies have sought to estimate the marginal cost-effectiveness of initial interferon treatment for chronic hepatitis C. The effects of treating patients with histologically mild chronic hepatitis C for 6 months with interferon was compared with no interferon treatment using a computer simulation model. Data were obtained from five prospective trials, natural history studies from the literature, and actual cost data for hepatitis C patients. After applying the currently recommended annual discount rate (3%), the computer model projects a $400 reduction in lifetime cost of care and a 1.5-year increase in life expectancy associated with interferon treatment. Economic savings derived from preventing future cases of cirrhosis and hepatocellular carcinoma more than offset the initial treatment cost. By preventing future liver complications in responders, interferon treatment should prolong life expectancy and reduce costs. When compared with other well-accepted medical interventions, interferon treatment should be considered "cost-effective." Economic rationales should not restrict the availability of interferon for patients with hepatitis C.
An interval-to-frequency converter for neurophysiological use

Abstract An interval-to-frequency converter is described. Design is simplified by use of a varistor, instead of a complicated diode network, to create a hyperbolic capacitor discharge. The capacitor voltage is sampled with a field-effect transistor at the end of the interval between two succeeding spikes in order to give an analog representation of the reciprocal of the interval.
Climate scientists and environmental interest groups: the intersection of expertise and advocacy

Whether through the accumulation of research suggesting that climate change is underway, or through critics' attacks on the objectivity of scientists, scientists play a key role in shaping public perceptions of climate change. As such, the actions of climate scientists have great potential to influence the policy process. We seek to understand one such action by scientists affiliating with environmental interest groups. We analyze the determinants of this activity by applying the interest group theory to climate change scientists using survey data. We posit that climate scientists who hold greater concern over climate change and who feel more efficacious are more likely to become active with environmental interest groups. The results from the empirical analysis indicate that climate scientists with a higher degree of efficacy are more likely participating with and supporting environmental interest groups; while, greater concern does not have the anticipated effect. These results have broad implications fo...
On mixed variational formulations in finite elasticity

In extension of a recent variational formulation of the problem of infinitesimal elasticity, with arbitrary variations of displacements andsome stresses [6], we use a recent consideration of variational formulations of finite elasticity, with arbitrary variations of translational and rotational displacements and of all stresses, or with arbitrary variations of these displacements and of three reactive stress measures [5], for the purpose of obtaining generalizations of the results in [6] which are valid for the equations of finite elasticity in terms of what we have called [5] “distinguished generalized” Piola stress components.
Computer-controlled hardware testing: A programmer's view of the test center

Computer-controlled hardware testing can be accomplished safely, dependably, and economically with the four-phase plan presented in this paper. The four phases are product design, product testers, tester programming, and data output. Usefulness of the plan increases if the designer, programmer, and management understand each others problems and do an adequate job of communicating.
A comparison of the effects of raloxifene and estrogen on bone in postmenopausal women.

Raloxifene HCl, a selective estrogen receptor modulator, has been shown to increase bone mineral density (BMD) and decrease biochemical markers of bone turnover in postmenopausal women without stimulatory effects on the breast and uterus. However, it is not known whether the changes in BMD and bone turnover are associated with changes at the tissue level, nor how changes with raloxifene compare with estrogen. In this randomized, double blind study, we evaluated the effects of raloxifene (Evista, 60 mg/day) or conjugated equine estrogens (CEE; Premarin, 0.625 mg/day) on bone architecture, bone turnover, and BMD. Iliac crest bone biopsies were obtained at baseline and at the end of the study after double tetracycline labeling and were analyzed for standard histomorphometric indexes. Serum and urinary biochemical markers of bone turnover were measured at baseline and at 4, 10, 18, and 24 weeks of treatment. Total body, lumbar spine, and hip BMD were measured at baseline and at the end of the study by dual energy x-ray absorptiometry. Activation frequency and bone formation rate/bone volume were significantly decreased from baseline in the CEE, but not in the raloxifene, group. Bone mineralization did not change in either group. Most markers of bone resorption and formation decreased in both groups, but to a greater degree in the CEE group (P < .05). Total body and lumbar spine BMD increased from baseline in both groups, with a greater increase in the CEE group (P < 0.05). Hip BMD significantly increased from baseline in the raloxifene group, but the change was not different from that in the CEE group. These results suggest that raloxifene reduces bone turnover and increases bone density, although to a lesser extent than CEE. Thus, raloxifene is an alternative to CEE for the prevention and treatment of osteoporosis in postmenopausal women.
Sterilization, High-Level Disinfection, and Environmental Cleaning

Failure to perform proper disinfection and sterilization of medical devices may lead to introduction of pathogens, resulting in infection. New techniques have been developed for achieving high-level disinfection and adequate environmental cleanliness. This article examines new technologies for sterilization and high-level disinfection of critical and semicritical items, respectively, and because semicritical items carry the greatest risk of infection, the authors discuss reprocessing semicritical items such as endoscopes and automated endoscope reprocessors, endocavitary probes, prostate biopsy probes, tonometers, laryngoscopes, and infrared coagulation devices. In addition, current issues and practices associated with environmental cleaning are reviewed.
Taylor dispersion of a solute in a microfluidic channel

The dispersion of a solute, traveling in a laminar-flow microfluidic channel, along the major axis of the channel is described by Taylor dispersion. It is shown that although diffusion of solute along the major axis is often neglected in constructing a governing transport equation, axial dispersion due to the laminar flow profile influences the distribution of solute in the channel. An expression for the effective Taylor dispersion coefficient due to the laminar velocity profile is derived and verified by comparing the predicted dispersion to results from a three-dimensional finite-element representation of the fluid dynamics and solute transport. Since the dispersion coefficient can be several orders of magnitude greater than the molecular diffusion coefficient, axial dispersion in microfluidic channels should not be casually neglected.
Silicalite-1 growth from clear solution: Effect of alcohol identity and content on growth kinetics.

In situ small-angle X-ray scattering (SAXS) is used to investigate the influence of alcohol identity and content on silicalite-1 growth from clear solutions at 368 K. Several tetraalkyl orthosilicates (Si(OR)4, R = Me, Pr, and Bu) are used to synthesize silicalite-1 from clear solution mixtures comparable to those previously investigated (i.e. 1:0.36:20 TEOS:TPAOH:H2O (TEOS = tetraethyl orthosilicate; TPAOH = tetrapropylammonium hydroxide), 368 K). All TPAOH−organosiloxane mixtures studied form silica nanoparticles after aging at room temperature for 24 h. Full-profile fitting analysis of the SAXS data indicates the particles are ellipsoidal and is inconsistent with the presence of “nanoslabs” or “nanoblocks”. Synthesis using TEOS as the silica source have an induction period of approximately 7.5 h and a growth rate of 1.90 ± 0.10 nm/h at 368 K. Changing the silica source to tetramethyl orthosilicate (TMOS) does not change the induction period; however the particle growth rate is decreased to 1.65 ± 0.09 ...
Chemosensory recognition by males of the Desert Pocket Mouse, Chaetodipus pencillatus to odors of various species of snakes

Studies were conducted to assess responses of the Desert Pocket Mouse Chaetodipus pencillatus, to chemosensory cues (treatment odors) associated with three naturally-occurring sympatric snake predators (Crotalus atrox, Pituophis melanoleucas, Elaphe guttata), and a snake that does not feed on mammals (Hypsiglena torquata), as well as an odorless control (water) and pungency control (cologne). Pocket mice were tested in a chamber where they were exposed to various treatments and their locomotor activity and defecation rate were recorded. Locomotor activity and defecation rates were significantly greater for mice exposed to odors associated with snake predators as compared to H. torquata or controls. There was no significant difference in responses of pocket mice to water or cologne treatments. Results suggest that because all test subjects had no prior experience with any of the snake species, their ability to detect and respond to odors associated with these predators must be innate.
A bounding box search algorithm for DEM simulation

Abstract In Discrete Element Method (DEM) simulations, the most costly operation performed by the program in terms of CPU time is often the process of identifying which pairs of particles are potentially in contact. Program performance can especially be degraded when the relative size difference between the smallest and largest discrete elements is greater than a factor of 2 to 5. Recently, particle-based searches with a hierarchy of cell spaces were proposed to eliminate the size-dependence problem (Peters et al. (2009) [1] ), He et al. (2007) [2] . Both methods allowed the cell size to be based on the diameter of the smallest particles, and the methods were found to be effective. In this paper, the authors evaluate the performance of a related but simpler algorithm dubbed the ‘bounding box search method’. The bounding box method entails identifying all cells which any part of a target particle may occupy, listing the target particle as present in those cells, and searching for potential contacts over the same set of cells (the ‘bounding box’). Where the hierarchy methods improve performance by creating multiple cell spaces based on particle sizes, the bounding box method uses only a single cell space, but allows the cell size to be based on the smallest particles, rather than the largest. To evaluate the performance of the bounding box algorithm, timed simulations were performed on systems with varying numbers of particles and particle size distributions, and runtimes were compared to identical systems simulated using a so-called ‘basic’ search algorithm, which places a target particle in a single cell and searches over all neighboring cells. Results presented herein show the bounding box approach to yield improved performance relative to the simple search method for most systems, especially those with the largest numbers of particles and least uniform size distributions. The effect of selected cell size is also examined, and it is shown that cell sizes between one and two times the smallest particle diameter yielded the best performance.
Cyclic AMP and theophylline enhance DNA synthesis in L cells stimulated with anti-actin IgG and [(IgG) 2 protein A] 2 complex by recruiting cells into S-phase

Surface binding of anti-actin IgG alone or in a Mr = 716 000 [(IgG)2Protein A]2 complex results in a stimulation of DNA synthesis and cell growth in L cells. Cyclic-AMP (0.01–1.0 mM) added to such cell cultures augmented DNA synthesis as measured by incorporation of [3H]thymidine into DNA. Theophylline (0.1–1.0 mM), a phosphodiesterase inhibitor which prevents enzymatic breakdown of cAMP, had similar effects, but cGMP (0.01–1.0 µM) reversed the effects of cAMP and theophylline upon DNA synthesis. Analysis of the cell cycle by flow cytometry revealed that antibody produced a shift (7%) of cells from the G1-phase to the S-phase (DNA-synthetic) of the cell cycle at 72 hr of incubation. Addition of cAMP (0.5 mM) to cell cultures, however, produced significant shifts of antibody stimulated cells from G1-phase to S-phase at all time points measured, i.e., 24 (12%),48 (22%),72 hr (23%). Thus, antibody recruited cells into S-phase of the cell cycle and cAMP greatly augmented the effect. These observations suggest that the mechanism of activation of L cell growth by antibody to surface antigens involves a recruitment of cells into the DNA-synthetic phase and that the effect may be mediated by cAMP.
Proteomics in heart failure: top-down or bottom-up?

The pathophysiology of heart failure (HF) is di- verse, owing to multiple etiologies and aberrations in a num- ber of cellular processes. Therefore, it is essential to under- stand how defects in the molecular pathways that mediate cellular responses to internal and external stressors function as a system to drive the HF phenotype. Mass spectrometry (MS)-based proteomics strategies have great potential for advancing our understanding of disease mechanisms at the systems level because proteins are the effector molecules for all cell functions and, thus, are directly responsible for deter- mining cell phenotype. Two MS-based proteomics strategies exist: peptide-based bottom-up and protein-based top-down proteomics—each with its own unique strengths and weak- nesses for interrogating the proteome. In this review, we will discuss the advantages and disadvantages of bottom-up and top-down MS for protein identification, quantification, and analysis of post-translational modifications, as well as high- light how both of these strategies have contributed to our understanding of the molecular and cellular mechanisms un- derlyingHF. Additionally, the challenges associated with both proteomics approaches will be discussed and insights will be offered regarding the future of MS-based proteomics in HF research.
OPTIMAL DESIGN OF SUPERCONDUCTING AC GENERATOR

Abstract The design philosophy and the optimization procedure used in the design of the superconducting generator are outlined and the effect of different parameters on the overall machine size and power density is examined. The effects of superconductor capability, environmental shield, type of rotor construction on the design of the machine are investigated. It is shown that the present day superconductors offer as much magnetic field generating capability as can be profitably used in synchronous machines and it is also shown that even in the “iron-free” or “air-core” superconducting machine, the design is dominated by the iron environmental shield.
Survey of two-dimensional electro-optical X-ray detectors

Abstract Electro-optical devices offer a flexible and modular approach to quantitative imaging X-ray detection. Such a detector typically consists of an energy converter coupled to a gain element which is followed by a readout device. This may, for example, be configured by coupling a scintillating screen to an image intensifier which is read by a TV camera. The large variety of commercially available energy converters, gain elements, and readout devices serve to limit the design problem to one of selecting the components, coupling them together and designing the appropriate electronics and software. The design criteria follow most directly from the nature of the particular X-ray detection problem being considered which, in turn, dictates which of two general modes the detector shall be operated in. In the photon counting mode, the gain element is of sufficient magnitude that each absorbed X-ray transmits a large and clearly recognizable signal to the readout device. This signal is real-time detected and allocated to memory. This has the advantages of high spatial resolution and high noise immunity; it has the disadvantage of a low maximum count rate. In another mode, termed the analog mode, the gain element is adjusted so that an individual x-ray makes a contribution comparable with the per-picture element readout noise on a readout device capable of integrating the signal from many X-rays. The magnitude of the integrated signal corresponds to the number of quanta incident. Since X-rays are not individually processed extremely high count rates can be accommodated. The primary disadvantages here is that the readout time lowers the device duty cycle. Hybrid modes are possible. The survey will emphasize the characteristics and principal limitations of the available components as applied toward synchrotron X-ray detection. Methods of coupling the components and modes of reading the final signal will be discussed. The literature pertaining to electro-optical devices that have been constructed will be briefly surveyed. Finally, the need for particular avenues of research and development will be outlined.
Needed research on current population trends.

Modern demography is criticized for its emphasis on reproductive biology and its failure to substantially incorporate the sociological determinents of fertility into attitudinal and contraceptive research. Current studies relate most to psychological theories while the prime factor in classical analysis of fertility declines in Western countries is industrialization which affords new options for social mobility and consequently motivates the more ambitious to reduce family responsibilities. Based in part on market research methods applied to a new type of consumer demand current antinatalist policy concentrates on the availability of contraceptive and family size attitudes. This family planning tactic has effectively cut fertility only where the socioeconomic environment itself generated antinatalist attitudes--e.g. a few atypical countries transitional to economic development (Taiwan South Korea Puerto Rico) and the minuscule westernized elites of the major underdeveloped countries. A crucial example is the failure of Indias 20-year program to completely reduce fertility rates. Research facilitating changes in institutional structures which would be antinatalist in effect includes the following topics: 1) illegitimate births; 2) socialization in family norms; 3) joint and nuclear family structure; 4) nonmarriage; 5) childless marriage; 6) age at marriage; 7) family subsidies; 8) antinatalist payments; 9) working wives.
The future of the US military presence in the Mediterranean

For a variety of reasons, the United States will gradually reduce its military presence in the Mediterranean basin. One of the principal reasons is that collectively the region is becoming less important economically to the United States. Trends in exports and imports between the United States and the states with Mediterranean coastlines indicate that the region accounts for a small and diminishing proportion of overall US trade. American overseas investment patterns appear to confirm this trend. This is important because the flag is more likely than ever before to follow economic interests. All other things being equal, a region that accounts for a small percentage of a nation's trade and investment will eventually be accorded a lower foreign policy priority than regions with greater trading volumes and higher investment values.
Plutonium-244 dating. VI: Initial ratios of plutonium to uranium in achondrites

Re-examination of all known xenon isotopic data for achondrites reveals that244Pu fission xenon can be resolved in about three-fourths of the meteorites of this class. The amounts of244Pu fission xenon found in these meteorites range from ca. 1–2 up to 20–40·10−12 ccSTP/g. These meteorites started to retain their xenon some 200–500 million years later than did the carbonaceous chondrites Allende, Groznaya, Mokoia, Murchison, Murray, and Renazzo, which began to retain their xenon over 4800 million years ago.
The Impact of Repeat HLA Mismatches on the Development of De Novo Donor Specific HLA Antbodies (DSA) in Lung ReTransplants

Purpose De Novo DSA is associated with increased risk of Bronchiolitis obliterans Syndrome (BOS) and allograft loss however the characteristics of De Novo DSA (DN DSA) that develops after repeat mismatched retransplant is unclear. We investigate the effect of repeat HLA mismatches on the development of DN DSA following lung retransplants. Methods and Materials Our study included re-transplants at our institute (n=15). We examined pre-Tx and DN DSA, as measured by single antigen Luminex beads specific to mismatched HLA antigens of the donor. Results Distribution of positive T cell flow crossmatch to the 2nd donor by pre-Tx DSA, mean number of mismatches against the 1st, 2nd donors and repeat MM are shown in table 1 . Characteristics of De novo DSA is shown in Table 2 . Twelve recipients had repeat mismatches. Five developed DN DSA after 1st donor, 2 developed DN DSA after 2nd donor (one of them within the first month) and none developed DN DSA to a repeat mismatch ( Table 2 ). Two individuals had a positive T cell crossmatch to the second donor. However, neither of these patients developed DSA after the second transplant. Conclusions Based on a realtively limited number of repeat lung transplants, it appears that repeat HLA mismatches are not associated with increased risk of development of de novo DSA to these antigens. The impact of repeat HLA mismatches on long term transplant outcomes has not been assessed in this study. These results are clinically relevant to donor selection criteria for lung retransplants and warrant further investigation in a larger cohort. Table 1 Pre-Tx DSA Mean # of 1st donor MM Mean # of 2nd donor MM Mean # of Rpt MM T Cell XM Neg (n=13) 12 (92%) 7.2 (4-11) 7.9 (6-10) 1.8 (0-4) T cell XM Pos (n=2) 1 (50%) 9.5 (7-12) 6.5 (6-7) 2.1 (1-2) Table 2 DSA to 1st Donor (n=5) DSA to 2nd Donor (n=2) DSA to Repeat MM (n=0) DSA Specificity Class I only 3 (60%) 2 (100%) 0 A23, A31, A68, B7, B45, Cw7 Class II Only 2 (40%) 0 (0%) 0 DRw53, DQ2 Class I + II 0 (0%) 0 (0%) 0 NA DSA in the first month 0 (0%) 1 (50%) 0 A31
Moral Philosophy in a Social Scientific Age: A Proposal to Reintegrate the Undergraduate Curriculum.

American higher education has been in almost perpetual crisis for several generations, with students experiencing fragmentation and loss of coherence across the curriculum. Most liberal arts colleges in the 19th century had a required senior course in “moral philosophy” to integrate the curriculum and prepare students for future leadership, but over a century ago the new science and social science disciplines ended these courses. Students now are trained in disciplinary silos, with little opportunity to integrate their studies after freshmen year general education courses. This paper proposes to reintegrate a student's undergraduate experience by having a required interdisciplinary senior capstone course, modeled on the old moral philosophy course but without its elitist and authoritarian methods. This new course would incorporate university values and the disciplines within it, in small interdisciplinary seminars designed around contemporary problems, which would provide students an opportunity to develo...
Oceanographic investigations using a sector-focusing cyclotron

Abstract The NRL sector-focusing cyclotron is a source of protons, deuterons, and helium nuclei with energies variable from a few MeV up to 75 MeV for protons. Proton activation of sea water salt enables one to measure calcium, strontium, bromine, and sulfur without chemical seperation and without interfering radiation from sodium or chlorine. Charged particle reactions are also useful in producing particular radioactive isotopes. Flourine-18 has been produced by the 16O(α, d)18F reaction on Li2O. Following a simple chemical procedure, carrier-free and uncomplexed 18F has been introduced into sea water for a variety of chemical oceanography experiments.
A Double-Delay-Line Clipped Linear Amplifier

A compact transistorized linear amplifier has been designed that is suitable for many radiation counting applications. The amplifier delivers symmetrical double-delay-line differentiated output pulses, up to ± 10 volts in amplitude with a differential non-linearity of ± 1%. It tolerates input signals 400 times full scale without producing spurious output pulses. Both a prompt output and one delayed by two microseconds are available. The clipping lines and the signal delay line are all terminated at both ends so that physically small, relatively imperfect delay lines can be employed. Five amplifiers occupy only 12-? inches in a standard 19 inch relay rack.
Visually impaired caregivers: perspectives from patient focus groups.

Abstract Background With the aging of the population, more persons who are severely visually impaired are now caring for a spouse or significant other. The purpose of this qualitative study is to learn more about this previously unreported, yet vulnerable, population of visually impaired caregivers. Methods Focus groups and 1-on-1 interviews were conducted with legally blind U.S. English-speaking adults who served as informal caregivers of adults. Visually impaired caregivers discussed the challenges of caregiving and how their visual impairment affected their caregiving responsibilities. Interview transcripts were analyzed using grounded theory. Standardized questionnaires captured demographic and social characteristics. Results Fourteen adults participated. Seven major themes emerged from the interviews: (1) impact of lack of transportation, (2) concern over care recipient's quality of life, (3) utilization of support, (4) all encompassing demand, (5) cyclical adaptations, (6) anxieties of the caregivers, and (7) positive aspects of caregiving. Conclusions Although visually impaired caregivers experience challenges similar to other caregivers, they differ in their report of added burden because of visual impairment, with extraordinary difficulty in transportation issues and the necessity of cyclical adaptations as their vision worsens. This is, to our knowledge, the first qualitative study of visually impaired caregivers and brings to light the unique problems faced by this special cohort of caregivers.
Incorporating Safety Risk in Early System Architecture Trade Studies

talking about safety analysis, we use the term “safety risk” in this paper where confusion would result.] This paper presents a new approach to preliminary hazard analysis that can be performed before system design selection and thus can influence key architectural decisions that will be impossible to change later in the system life cycle. The approach is illustrated through a concept evaluation and refinement study for the new NASA space exploration.
Measuring elementary teacher stress and coping in the classroom: Validity evidence for the Classroom Appraisal of Resources and Demands

The Classroom Appraisal of Resources and Demands (CARD, elementary version) was used to investigate teacher stress among a sample of elementary teachers (n = 521). The CARD measures teacher stress by examining the subjective experience of both classroom demands and resources provided by the school, and thereby attempts to capture the situationally specific nature of teacher stress. This study attempted to examine whether the CARD can provide reliable and valid information that addresses the call by experts in the field of teacher stress research for measures that consider each teacher’s specific occupational circumstances. Specifically, the factor structure of the CARD was supported empirically. Further evidence was offered for the construct and concurrent validity by correlations between CARD scales scores and other measures theoretically relevant to teacher well-being: general health, teacher efficacy, self-critical attitudes, and burnout symptoms. C � 2009 Wiley Periodicals, Inc.
Optimists vs Pessimists: Survival Rate Among Medical Patients Over a 30-Year Period

Objective To examine explanatory style (how people explain life events) as a risk factor for early death, using scores from the Optimism-Pessimism scale of the Minnesota Multiphasic Personality Inventory (MMPI). Subjects and Methods A total of 839 patients completed the MMPI between 1962 and 1965 as self-referred general medical patients. Thirty years later, the vital status of each of these patients was ascertained. Results Of the 839 patients, 124 were classified as optimistic, 518 as mixed, and 197 as pessimistic. Follow-up was available for 723 patients. Among these, a 10-point T-score increase on the Optimism-Pessimism scale (eg, more pessimistic) was associated with a 19% increase in the risk of mortality. Conclusion A pessimistic explanatory style, as measured by the Optimism-Pessimism scale of the MMPI, is significantly associated with mortality.
Plasma sctence and engineering at NSF

Summary form only given. Presents a perspective of the breath of fundamental plasma science and engineering that the National Science Foundation supports through its Directorates for Engineering, Mathematical and Physical Sciences, Geosciences, and the Office of Polar Programs. 1 plan also to discuss the diverse interests and commitment within the Foundation to maintaining thc vitality of research and education activities in this field.
Vasopressin and phorbol‐12, 13‐dibutyrate inhibit glucagon‐ or cyclic AMP‐stimulated taurocholate uptake in isolated rat hepatocytes

Bile salt uptake by hepatocytes is modulated in part by changes in intracellular cyclic AMP. We studied the effect of activation of protein kinase C on cyclic AMP-mediated taurocholate uptake in isolated rat hepatocytes. Both dibutyryl cyclic AMP (2 × 10−6 mol/L) and glucagon (10−6 mol/L), which increase intracellular cyclic AMP, enhanced the initial uptake rate of taurocholate into hepatocytes, with maximal increases of 45% to 50% over the basal uptake rate. Vasopressin (10−9 mol/L), a hormone known to activate protein kinase C, and phorbol-12, 13-dibutyrate (10−5 mol/L) significantly inhibited the glucagon-stimulated increase in taurocholate uptake rate (72% ± 10% and 105% ± 13% inhibition, respectively). Basal (unstimulated) taurocholate uptake rate was not affected by vasopressin or phorbol-12, 13-dibutyrate. Down-regulation of the glucagon-stimulated transport was rapid and persisted during the 20-min experimental period. Angiotensin II had a similar but more transient inhibitory effect. Vasopressin and phorbol-12, 13-dibutyrate suppression of glucagon-stimulated taurocholate uptake rate was not accompanied by diminished cyclic AMP levels. Moreover, vasopressin and phorbol-12, 13-dibutyrate inhibited dibutyryl cyclic AMP-stimulated taurocholate uptake rate can be dissociated from alterations in the cyclic AMP levels. (Hepatology 1994;20:159–165.)
Macrotasking and microtasking a Navier-Stokes algorithm on the Cray-2

This paper presents the results of macrotasking and microtasking a Navier-Stokes algorithm on the Cray-2. The algorithm is a compact difference scheme for the solution of the incompressible, two-dimensional, time dependent Navier-Stokes equations. Two implementations of multitasking on the Cray-2 are considered. These are: macrotasking (parallelism at the subroutine level) and microtasking (parallelism at the do-loop level). These two techniques are briefly described. The implementation of the algorithm is discussed in relation to these techniques and the results for three problem sizes are presented. The timing results for both techniques are in general comparable with differences ranging between 2% to 14% depending on the problem size. The best achieved speedup in a dedicated environment is 3.62 for macrotasking and 3.32 for microtasking. Finally, comparisons are made and conclusions are drawn.
A study of the thermal decomposition of biguanidinium diperchlorate using thermogravimetry and mass spectroscopy

The thermal decomposition of biguanidinium diperchlorate has been studied by thermogravimetry in a nitrogen atmosphere and by mass spectrometry. The kinetics of the decomposition have been found from these experiments to be very rapid and exothermic. A first order (F1) mechanism has been fitted to the decomposition up to the point of inflection.