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Showing papers by "University of Washington published in 1994"


Journal ArticleDOI
TL;DR: The approach described in this manuscript provides a convenient method to interpret tandem mass spectra with known sequences in a protein database.

6,317 citations


Journal ArticleDOI
K. Hagiwara, Ken Ichi Hikasa1, Koji Nakamura, Masaharu Tanabashi1, M. Aguilar-Benitez, Claude Amsler2, R. M. Barnett3, Patricia R. Burchat4, C. D. Carone5, C. Caso, G. Conforto6, Olav Dahl3, Michael Doser7, Semen Eidelman8, Jonathan L. Feng9, L. K. Gibbons10, Maury Goodman11, Christoph Grab12, D. E. Groom3, Atul Gurtu7, Atul Gurtu13, K. G. Hayes14, J. J. Herna`ndez-Rey15, K. Honscheid16, Christopher Kolda17, Michelangelo L. Mangano7, David Manley18, Aneesh V. Manohar19, John March-Russell7, Alberto Masoni, Ramon Miquel3, Klaus Mönig, Hitoshi Murayama20, Hitoshi Murayama3, S. Sánchez Navas12, Keith A. Olive21, Luc Pape7, C. Patrignani, A. Piepke22, Matts Roos23, John Terning24, Nils A. Tornqvist23, T. G. Trippe3, Petr Vogel25, C. G. Wohl3, Ron L. Workman26, W-M. Yao3, B. Armstrong3, P. S. Gee3, K. S. Lugovsky, S. B. Lugovsky, V. S. Lugovsky, Marina Artuso27, D. Asner28, K. S. Babu29, E. L. Barberio7, Marco Battaglia7, H. Bichsel30, O. Biebel31, Philippe Bloch7, Robert N. Cahn3, Ariella Cattai7, R. S. Chivukula32, R. Cousins33, G. A. Cowan34, Thibault Damour35, K. Desler, R. J. Donahue3, D. A. Edwards, Victor Daniel Elvira, Jens Erler36, V. V. Ezhela, A Fassò7, W. Fetscher12, Brian D. Fields37, B. Foster38, Daniel Froidevaux7, Masataka Fukugita39, Thomas K. Gaisser40, L. Garren, H.-J. Gerber12, Frederick J. Gilman41, Howard E. Haber42, C. A. Hagmann28, J.L. Hewett4, Ian Hinchliffe3, Craig J. Hogan30, G. Höhler43, P. Igo-Kemenes44, John David Jackson3, Kurtis F Johnson45, D. Karlen, B. Kayser, S. R. Klein3, Konrad Kleinknecht46, I.G. Knowles47, P. Kreitz4, Yu V. Kuyanov, R. Landua7, Paul Langacker36, L. S. Littenberg48, Alan D. Martin49, Tatsuya Nakada50, Tatsuya Nakada7, Meenakshi Narain32, Paolo Nason, John A. Peacock47, Helen R. Quinn4, Stuart Raby16, Georg G. Raffelt31, E. A. Razuvaev, B. Renk46, L. Rolandi7, Michael T Ronan3, L.J. Rosenberg51, Christopher T. Sachrajda52, A. I. Sanda53, Subir Sarkar54, Michael Schmitt55, O. Schneider50, Douglas Scott56, W. G. Seligman57, Michael H. Shaevitz57, Torbjörn Sjöstrand58, George F. Smoot3, Stefan M Spanier4, H. Spieler3, N. J. C. Spooner59, Mark Srednicki60, A. Stahl, Todor Stanev40, M. Suzuki3, N. P. Tkachenko, German Valencia61, K. van Bibber28, Manuella Vincter62, D. R. Ward63, Bryan R. Webber63, M R Whalley49, Lincoln Wolfenstein41, J. Womersley, C. L. Woody48, O. V. Zenin 
Tohoku University1, University of Zurich2, Lawrence Berkeley National Laboratory3, Stanford University4, College of William & Mary5, University of Urbino6, CERN7, Budker Institute of Nuclear Physics8, University of California, Irvine9, Cornell University10, Argonne National Laboratory11, ETH Zurich12, Tata Institute of Fundamental Research13, Hillsdale College14, Spanish National Research Council15, Ohio State University16, University of Notre Dame17, Kent State University18, University of California, San Diego19, University of California, Berkeley20, University of Minnesota21, University of Alabama22, University of Helsinki23, Los Alamos National Laboratory24, California Institute of Technology25, George Washington University26, Syracuse University27, Lawrence Livermore National Laboratory28, Oklahoma State University–Stillwater29, University of Washington30, Max Planck Society31, Boston University32, University of California, Los Angeles33, Royal Holloway, University of London34, Université Paris-Saclay35, University of Pennsylvania36, University of Illinois at Urbana–Champaign37, University of Bristol38, University of Tokyo39, University of Delaware40, Carnegie Mellon University41, University of California, Santa Cruz42, Karlsruhe Institute of Technology43, Heidelberg University44, Florida State University45, University of Mainz46, University of Edinburgh47, Brookhaven National Laboratory48, Durham University49, University of Lausanne50, Massachusetts Institute of Technology51, University of Southampton52, Nagoya University53, University of Oxford54, Northwestern University55, University of British Columbia56, Columbia University57, Lund University58, University of Sheffield59, University of California, Santa Barbara60, Iowa State University61, University of Alberta62, University of Cambridge63
TL;DR: This biennial Review summarizes much of Particle Physics using data from previous editions, plus 2205 new measurements from 667 papers, and features expanded coverage of CP violation in B mesons and of neutrino oscillations.
Abstract: This biennial Review summarizes much of Particle Physics. Using data from previous editions, plus 2205 new measurements from 667 papers, we list, evaluate, and average measured properties of gauge bosons, leptons, quarks, mesons, and baryons. We also summarize searches for hypothetical particles such as Higgs bosons, heavy neutrinos, and supersymmetric particles. All the particle properties and search limits are listed in Summary Tables. We also give numerous tables, figures, formulae, and reviews of topics such as the Standard Model, particle detectors, probability, and statistics. This edition features expanded coverage of CP violation in B mesons and of neutrino oscillations. For the first time we cover searches for evidence of extra dimensions (both in the particle listings and in a new review). Another new review is on Grand Unified Theories. A booklet is available containing the Summary Tables and abbreviated versions of some of the other sections of this full Review. All tables, listings, and reviews (and errata) are also available on the Particle Data Group website: http://pdg.lbl.gov.

5,143 citations


Journal ArticleDOI
TL;DR: In pregnant women with mildly symptomatic HIV disease and no prior treatment with antiretroviral drugs during the pregnancy, a regimen consisting of zidovudine given ante partum and intra partum to the mother and to the newborn for six weeks reduced the risk of maternal-infant HIV transmission by approximately two thirds.
Abstract: Background and Methods Maternal-infant transmission is the primary means by which young children become infected with human immunodeficiency virus type 1 (HIV). We conducted a randomized, double-blind, placebo-controlled trial of the efficacy and safety of zidovudine in reducing the risk of maternal-infant HIV transmission. HIV-infected pregnant women (14 to 34 weeks' gestation) with CD4+ T-lymphocyte counts above 200 cells per cubic millimeter who had not received antiretroviral therapy during the current pregnancy were enrolled. The zidovudine regimen included antepartum zidovudine (100 mg orally five times daily), intrapartum zidovudine (2 mg per kilogram of body weight given intravenously over a one-hour period, then 1 mg per kilogram per hour until delivery), and zidovudine for the newborn (2 mg per kilogram orally every six hours for six weeks). Infants with at least one positive HIV culture of peripheral-blood mononuclear cells were classified as HIV-infected. Results From April 1991 through Decemb...

3,604 citations


Journal ArticleDOI
21 Oct 1994-Cell
TL;DR: It is shown that the inhibition of metastases by a primary mouse tumor is mediated, at least in part, by angiostatin, and a corresponding fragment of human plasminogen has similar activity.

3,516 citations


Journal ArticleDOI
TL;DR: In this paper, a generalization of the single soil layer variable infiltration capacity (VIC) land surface hydrological model previously implemented in the Geophysical Fluid Dynamics Laboratory (GFDL) general circulation model (GCM) is described.
Abstract: A generalization of the single soil layer variable infiltration capacity (VIC) land surface hydrological model previously implemented in the Geophysical Fluid Dynamics Laboratory (GFDL) general circulation model (GCM) is described. The new model is comprised of a two-layer characterization of the soil column, and uses an aerodynamic representation of the latent and sensible heat fluxes at the land surface. The infiltration algorithm for the upper layer is essentially the same as for the single layer VIC model, while the lower layer drainage formulation is of the form previously implemented in the Max-Planck-Institut GCM. The model partitions the area of interest (e.g., grid cell) into multiple land surface cover types; for each land cover type the fraction of roots in the upper and lower zone is specified. Evapotranspiration consists of three components: canopy evaporation, evaporation from bare soils, and transpiration, which is represented using a canopy and architectural resistance formulation. Once the latent heat flux has been computed, the surface energy balance is iterated to solve for the land surface temperature at each time step. The model was tested using long-term hydrologic and climatological data for Kings Creek, Kansas to estimate and validate the hydrological parameters, and surface flux data from three First International Satellite Land Surface Climatology Project Field Experiment (FIFE) intensive field campaigns in the summer-fall of 1987 to validate the surface energy fluxes.

3,297 citations


Journal ArticleDOI
TL;DR: In this article, the authors examined the abnormal accruals of a sample of 94 firms that reported debt covenant violations in annual reports and found that debt covenants influence accounting choices in the year preceding and the year of violation.

2,850 citations


Journal ArticleDOI
14 Jan 1994-Cell
TL;DR: Results show that the process of positive selection is exquisitely peptide specific and sensitive to extremely low ligand density and support the notion that low efficacy ligands mediate positive selection.

2,715 citations


Journal ArticleDOI
16 Dec 1994-Science
TL;DR: New insights in understanding of the cell cycle reveal how fidelity is normally achieved by the coordinated activity of cyclin-dependent kinases, checkpoint controls, and repair pathways and how this fidelity can be abrogated by specific genetic changes.
Abstract: Multiple genetic changes occur during the evolution of normal cells into cancer cells. This evolution is facilitated in cancer cells by loss of fidelity in the processes that replicate, repair, and segregate the genome. Recent advances in our understanding of the cell cycle reveal how fidelity is normally achieved by the coordinated activity of cyclin-dependent kinases, checkpoint controls, and repair pathways and how this fidelity can be abrogated by specific genetic changes. These insights suggest molecular mechanisms for cellular transformation and may help to identify potential targets for improved cancer therapies.

2,514 citations


Journal ArticleDOI
TL;DR: Raster3D Version 2.0 is a program suite for the production of photorealistic molecular graphics images, and is particularly suited for use in producing large raster images of macromolecules for output to a film recorder or high-quality color printer.
Abstract: Raster3D Version 2.0 is a program suite for the production of photorealistic molecular graphics images. The code is hardware independent, and is particularly suited for use in producing large raster images of macromolecules for output to a film recorder or high-quality color printer. The Raster3D suite contains programs for composing illustrations of space-filling models, ball-and-stick models and ribbon-and-cylinder representations. It may also be used to render figures composed using other graphics tools, notably the widely used program Molscript [Kraulis (1991). J. Appl. Cryst. 24, 946-950].

2,492 citations


Journal ArticleDOI
TL;DR: It is argued that to best comprehend many data sets, plotting judiciously selected sample statistics with associated confidence intervals can usefully supplement, or even replace, standard hypothesis-testing procedures.
Abstract: We argue that to best comprehend many data sets, plotting judiciously selected sample statistics with associated confidence intervals can usefully supplement, or even replace, standard hypothesis-testing procedures. We note that most social science statistics textbooks limit discussion of confidence intervals to their use in between-subject designs. Our central purpose in this article is to describe how to compute an analogous confidence interval that can be used in within-subject designs. This confidence interval rests on the reasoning that because between-subject variance typically plays no role in statistical analyses of within-subject designs, it can legitimately be ignored; hence, an appropriate confidence interval can be based on the standard within-subject error term-that is, on the variability due to the subject × condition interaction. Computation of such a confidence interval is simple and is embodied in Equation 2 on p. 482 of this article. This confidence interval has two useful properties. First, it is based on the same error term as is the corresponding analysis of variance, and hence leads to comparable conclusions. Second, it is related by a known factor (√2) to a confidence interval of the difference between sample means; accordingly, it can be used to infer the faith one can put in some pattern of sample means as a reflection of the underlying pattern of population means. These two properties correspond to analogous properties of the more widely used between-subject confidence interval.

2,432 citations


Journal ArticleDOI
TL;DR: In this article, the authors have shown evidence of a positive relationship between market orientation and performance and suggested that competitive environment could moderate this relationship, but they did not consider the impact of competition on market orientation.
Abstract: Recent studies have shown evidence of a positive relationship between market orientation and performance. However, some scholars have suggested that competitive environment could moderate this rela...

Journal ArticleDOI
TL;DR: A strategy of initial CABG surgery is associated with lower mortality than one of medical management with delayed surgery if necessary, especially in high-risk and medium- risk patients with stable coronary heart disease, and in low-risk patients, the limited data show a non-significant trend towards greater mortality with CABGs.

Journal ArticleDOI
TL;DR: In service settings, customer satisfaction is often influenced by the quality of the interpersonal interaction between the customer and the contact employee as discussed by the authors, which can be identified as one of the most important factors for customer satisfaction.
Abstract: In service settings, customer satisfaction is often influenced by the quality of the interpersonal interaction between the customer and the contact employee. Previous research has identified the so...

Journal ArticleDOI
TL;DR: The apoE-deficient mouse contains the entire spectrum of lesions observed during atherogenesis and is the first mouse model to develop lesions similar to those in humans.
Abstract: Initial description of apolipoprotein (apo) E-deficient transgenic mice demonstrated the development of severe hypercholesterolemia due to probable delayed clearance of large atherogenic particles from the circulation. Examination of these mice demonstrated foam cell accumulation in the aortic root and pulmonary arteries by 10 weeks of age. In the present study, the animals were fed either chow or a high-fat, Western-type diet and examined at ages ranging from 6 to 40 weeks. Gross examination by dissection microscopy revealed a predilection for development of lesions in the aortic root, at the lesser curvature of the aortic arch, the principal branches of the aorta, and in the pulmonary and carotid arteries. Monocyte attachment to endothelial cells was observed by light and electron microscopic examination at 6 weeks, the earliest time point examined. Foam cell lesions developed as early as 8 weeks, and after 15 weeks advanced lesions (fibrous plaques) were observed. The latter consisted of a fibrous cap containing smooth muscle cells surrounded by connective tissue matrix that covered a necrotic core with numerous foamy macrophages. Mice fed the Western-type diet generally had more advanced lesions than those fed a chow diet. The apoE-deficient mouse contains the entire spectrum of lesions observed during atherogenesis and is the first mouse model to develop lesions similar to those in humans. This model should provide numerous opportunities to study the pathogenesis and therapy of atherosclerosis in a small, genetically defined animal.

Journal ArticleDOI
TL;DR: Self-reports of smoking are accurate in most studies, but biochemical assessment, preferably with cotinine plasma, should be considered in intervention studies and student populations to improve accuracy.
Abstract: OBJECTIVES. The purpose of this study was to identify circumstances in which biochemical assessments of smoking produce systematically higher or lower estimates of smoking than self-reports. A secondary aim was to evaluate different statistical approaches to analyzing variation in validity estimates. METHODS. Literature searches and personal inquiries identified 26 published reports containing 51 comparisons between self-reported behavior and biochemical measures. The sensitivity and specificity of self-reports of smoking were calculated for each study as measures of accuracy. RESULTS. Sensitivity ranged from 6% to 100% (mean = 87.5%), and specificity ranged from 33% to 100% (mean = 89.2%). Interviewer-administered questionnaires, observational studies, reports by adults, and biochemical validation with cotinine plasma were associated with higher estimates of sensitivity and specificity. CONCLUSIONS. Self-reports of smoking are accurate in most studies. To improve accuracy, biochemical assessment, prefera...

Journal ArticleDOI
TL;DR: A formalism for active concept learning called selective sampling is described and it is shown how it may be approximately implemented by a neural network.
Abstract: Active learning differs from “learning from examples” in that the learning algorithm assumes at least some control over what part of the input domain it receives information about. In some situations, active learning is provably more powerful than learning from examples alone, giving better generalization for a fixed number of training examples. In this article, we consider the problem of learning a binary concept in the absence of noise. We describe a formalism for active concept learning called selective sampling and show how it may be approximately implemented by a neural network. In selective sampling, a learner receives distribution information from the environment and queries an oracle on parts of the domain it considers “useful.” We test our implementation, called an SG-network, on three domains and observe significant improvement in generalization.

Journal ArticleDOI
06 Jul 1994-JAMA
TL;DR: It is concluded that ulcer patients with H. pylori infection require treatment with antimicrobial agents in addition to antisecretory drugs whether on first presentation with the illness or on recurrence.
Abstract: The National Institutes of Health Consensus Development Conference onHelicobacter pyloriin Peptic Ulcer Disease brought together specialists in gastroenterology, surgery, infectious diseases, epidemiology, and pathology, as well as the public to address the following questions: (1) What is the causal relationship ofH pylorito upper gastrointestinal disease? (2) How does one diagnose and eradicateH pyloriinfection? (3) Does eradication ofH pyloriinfection benefit the patient with peptic ulcer disease? (4) What is the relationship betweenH pyloriinfection and gastric malignancy? (5) WhichH pylori—infected patients should be treated? (6) What are the most important questions that must be addressed by future research inH pyloriinfections? Following 1½ days of presentations by experts and discussion by the audience, a consensus panel weighed the evidence and prepared their consensus statement. Among their findings, the consensus panel concluded that (1) ulcer patients withH pyloriinfection require treatment with antimicrobial agents in addition to antisecretory drugs whether on first presentation with the illness or on recurrence; (2) the value of treating of nonulcerative dyspepsia patients withH pyloriinfection remains to be determined; and (3) the interesting relationship betweenH pyloriinfection and gastric cancers requires further exploration. (JAMA. 1994;272:65-69)

BookDOI
TL;DR: In this paper, Terman's Question: What Makes for Marital Happiness? The View From Observational Methods was raised from observations from physiological and behavioral methods, and a balance theory of marriage was proposed.
Abstract: Contents: Introduction. What Makes Some Marriages Magical and Some Miserable? Raising the Questions. Terman's Question: What Makes for Marital Happiness? The View From Observational Methods. Longitudinal Change in Marital Happiness: Observing Physiology as Well as Marital Interaction. Marital Processes That Predict Dissolution. In What Sense Are Regulated Couples Regulated? Is Conflict Avoidance Dysfunctional? Conflict Avoidance and the Behavior of the Listener: Toward a Typology of Marriage. There Are Two Types of Conflict Engagers. A Balance Theory of Marriage. There Are Two Types of Nonregulated Couples. Male Withdrawal From Marital Conflict. Replication and Extension. Physiology During Marital Interaction. Toward a Comprehensive Theory of Marital Stability. Eight-Year Longitudinal Follow-Up Study. Recommendations for a Stable Marriage. Epilogue. Appendix: The Observational Coding Systems.

Journal ArticleDOI
TL;DR: In this article, the authors consider the problem of model selection and accounting for model uncertainty in high-dimensional contingency tables, motivated by expert system applications, and propose a panacea by the standard Bayesian formalism that averages the posterior distributions of the quantity of interest under each of the models, weighted by their posterior model probabilities.
Abstract: We consider the problem of model selection and accounting for model uncertainty in high-dimensional contingency tables, motivated by expert system applications. The approach most used currently is a stepwise strategy guided by tests based on approximate asymptotic P values leading to the selection of a single model; inference is then conditional on the selected model. The sampling properties of such a strategy are complex, and the failure to take account of model uncertainty leads to underestimation of uncertainty about quantities of interest. In principle, a panacea is provided by the standard Bayesian formalism that averages the posterior distributions of the quantity of interest under each of the models, weighted by their posterior model probabilities. Furthermore, this approach is optimal in the sense of maximizing predictive ability. But this has not been used in practice, because computing the posterior model probabilities is hard and the number of models is very large (often greater than 1...

Journal ArticleDOI
TL;DR: The model of employee turnover described in this article applies constructs and concepts from decision making, statistics, and social psychology to facilitate understanding and to redirect theory development and empirical research, and five specific contributions of the model are suggested, and recommendations for empirical testing and future research are offered.
Abstract: The model of employee turnover described in this paper applies constructs and concepts from decision making, statistics, and social psychology to facilitate understanding and to redirect theory development and empirical research. The process of employee turnover is modeled by four distinctive decision paths; each decision path involves distinctive foci, psychological processes, and external events. Further, five specific contributions of the model are suggested, and recommendations for empirical testing and future research are offered.

Journal ArticleDOI
TL;DR: Using self-consistent field theory, microphases of diblock copolymers are examined and a stable gyroid phase is found which occurs between the lamellar and hexagonal ones and terminates at a triple point.
Abstract: Using self-consistent field theory, we examine microphases of diblock copolymers and find, in addition to lamellar, hexagonal, and cubic phases, a stable gyroid phase which occurs between the lamellar and hexagonal ones. It terminates at a triple point, with a lamellar to hexagonal transition occurring in the weak-segregation limit. Other phases of experimental interest are studied, and we describe the regions in which they are most nearly stable.

Journal ArticleDOI
TL;DR: Coded home videotapes of 11 autistic and 11 normally developing children's first year birthday parties for social, affective, joint attention, and communicative behaviors and for specific autistic symptoms found autistic children displayed significantly fewer social and joint attention behaviors and significantly more autistic symptoms.
Abstract: Coded home videotapes of 11 autistic and 11 normally developing children's first year birthday parties for social, affective, joint attention, and communicative behaviors and for specific autistic symptoms. Autistic children displayed significantly fewer social and joint attention behaviors and significantly more autistic symptoms. In combination, four behaviors correctly classified 10 of 11 autistic children and 10 of 11 normal children. These behaviors consisted of pointing, showing objects, looking at others, and orienting to name.

Journal ArticleDOI
TL;DR: The early lesion of “degenerative” aortic stenosis is an active inflammatory process with some similarities (lipid deposition, macrophage and T-cell infiltration, and basement membrane disruption) and some dissimilarities (presence of prominent mineralization and small numbers of smooth muscle cells) to atherosclerosis.
Abstract: BACKGROUNDNonrheumatic stenosis of trileaflet aortic valves, often termed senile or calcific valvular aortic stenosis, is considered a "degenerative" process, but little is known about the cellular or molecular factors that mediate its developmentMETHODS AND RESULTSTo characterize the developing aortic valvular lesion, we performed histological and immunohistochemical studies on Formalin-fixed and methanol-Carnoy's-fixed paraffin-embedded aortic valve leaflets or on frozen sections obtained at autopsy from 27 adults (age, 46 to 82 years) with normal leaflets (n = 6), mild macroscopic leaflet thickening (n = 15), or clinical aortic stenosis (n = 6) Focal areas of thickening ("early lesions") were characterized by (1) subendothelial thickening on the aortic side of the leaflet, between the basement membrane (PAS-positive) and elastic lamina (Verhoeff-van Gieson), (2) the presence of large amounts of intracellular and extracellular neutral lipids (oil red O) and fine, stippled mineralization (von Kossa), a

Journal ArticleDOI
TL;DR: A robust learning algorithm is proposed and applied to recurrent neural networks, NARMA(p,q), which show advantages over feedforward neural networks for time series with a moving average component and are shown to give better predictions than neural networks trained on unfiltered time series.
Abstract: We propose a robust learning algorithm and apply it to recurrent neural networks. This algorithm is based on filtering outliers from the data and then estimating parameters from the filtered data. The filtering removes outliers from both the target function and the inputs of the neural network. The filtering is soft in that some outliers are neither completely rejected nor accepted. To show the need for robust recurrent networks, we compare the predictive ability of least squares estimated recurrent networks on synthetic data and on the Puget Power Electric Demand time series. These investigations result in a class of recurrent neural networks, NARMA(p,q), which show advantages over feedforward neural networks for time series with a moving average component. Conventional least squares methods of fitting NARMA(p,q) neural network models are shown to suffer a lack of robustness towards outliers. This sensitivity to outliers is demonstrated on both the synthetic and real data sets. Filtering the Puget Power Electric Demand time series is shown to automatically remove the outliers due to holidays. Neural networks trained on filtered data are then shown to give better predictions than neural networks trained on unfiltered time series. >

Journal ArticleDOI
16 Jun 1994-Nature
TL;DR: The functional cloning of a murine complementary DNA encoding a ligand for the receptor encoded by the c-mpl proto-oncogene is reported, and results strongly suggest that theligand for c-Mpl is thrombopoietin.
Abstract: The major regulator of circulating platelet levels is believed to be a cytokine termed thrombopoietin. It is thought to be a lineage-specific cytokine affecting the proliferation and maturation of committed cells resulting in the production of megakaryocytes and platelets. Despite considerable efforts by a number of laboratories, the unequivocal identification of thrombopoietin has proven elusive. Here we report the functional cloning of a murine complementary DNA encoding a ligand for the receptor encoded by the c-mpl proto-oncogene (c-Mpl). The encoded polypeptide has a predicted molecular mass of 35,000 (M(r) 35K). The protein has a novel two-domain structure with an amino-terminal domain homologous with erythropoietin and a carboxy-terminal domain rich in serine, threonine and proline residues and containing seven potential N-linked glycosylation sites. Intraperitoneal injections of mice with recombinant protein increase circulating platelet levels by greater than fourfold after 7 days. These results along with those presented in the accompanying report strongly suggest that the ligand for c-Mpl is thrombopoietin.

Journal ArticleDOI
TL;DR: In this paper, the authors found that children, young adults, and older adults chose between immediate and delayed monetary rewards, and the amount of the delayed reward was held constant while its delay was varied.
Abstract: In this study, children, young adults, and older adults chose between immediate and delayed hypothetical monetary rewards The amount of the delayed reward was held constant while its delay was varied All three age groups showed delay discounting, that is, the amount of an immediate reward judged to be of equal value to the delayed reward decreased as a function of delay The rate of discounting was highest for children and lowest for older adults, predicting a life-span developmental trend toward increased self-control Discounting of delayed rewards by all three age groups was well described by a single function with age-sensitive parameters (all R2s > 94) Thus, even though there are quantitative age differences in delay discounting, the existence of an age-invariant form of discount function suggests that the process of choosing between rewards of different amounts and delays is qualitatively similar across the life span

Journal ArticleDOI
01 Aug 1994-Nature
TL;DR: The authors showed that the modelled small-scale properties of CDM are fundamentally incompatible with recent observations10−13 of dwarf galaxies, which are thought to be completely dominated by dark matter on scales larger than a kiloparsec.
Abstract: THERE are two different types of missing (dark) matter: the unseen matter needed to explain the high rotation velocities of atomic hydrogen in the outer parts of spiral galaxies1,2, and the much larger amount of (non-baryonic) matter needed to prevent the universe from expanding forever1 (producing either a ‘flat’ or a ‘closed’ Universe)3. Several models have been proposed to provide the dark matter required within galaxy haloes for a flat universe, of which cold dark matter (CDM) has proved the most successful at reproducing the observed large-scale structure of the Universe4–6. CDM belongs to a class of non-relativistic particles that interact primarily through gravity, and are named dissipationless because they cannot dissipate energy (baryonic particles can lose energy by emitting electromagnetic radiation). Here I show that the modelled small-scale properties of CDM7–9 are fundamentally incompatible with recent observations10–13 of dwarf galaxies, which are thought to be completely dominated by dark matter on scales larger than a kiloparsec. Thus, the hypothesis that dark matter is predominantly cold seems hard to sustain.

Journal ArticleDOI
TL;DR: The theoretical model of how people's perceptions in these domains are positively biased is reviewed, certain misconceptions in its empirical application are correct, and criticisms made by Colvin and Block are addressed.
Abstract: In 1988, we published an article that challenged the notion that accurate perceptions of self and the world are essential for mental health (Taylor & Brown, 1988). We argued instead that people's perceptions in these domains are positively biased and that these positive illusions promote psychological well-being. In the current article, we review our theoretical model, correct certain misconceptions in its empirical application, and address the criticisms made by Colvin and Block. Taylor and Brown's (1988) model of mental health maintains that certain positive illusions are highly prevalent in normal thought and predictive of criteria traditionally associated with mental health. The work initially derived from research with cancer patients (Taylor, 1983) but was integrated in the 1988 essay with literature on social cognition, suggesting that the formulation could also make sense of previously anomalous and somewhat unrelated errors and biases in human thought. As is the case with any theoretical model, the goal of the article was to generate research. On this ground, the model appears to have been quite successful. According to Colvin and Block's estimation, approximately 250 studies have made use of the formulation. Given its popularity and influence, a critical examination of the Taylor and Brown argument is appropriate. In this article, we (a) review some of the central points of our theoretical model; (b) examine Colvin and Block's article in view of these issues; (c) present research germane to our thesis but not discussed by Colvin and Block; and (d) raise some important issues that have yet to be resolved. As before, our aim is to contribute to an informed dialogue regarding the nature of psychological well-being.

Journal ArticleDOI
16 Jun 1994-Nature
TL;DR: The ligand for c-Mpl is relatively lineage specific, works both alone and synergistically with early acting cytokines to support megakaryocyte colony formation, and acts at a late stage of development to increase megakarianocyte size, polyploidization and expression of differentiation markers.
Abstract: The development of blood cells including expansion of megakaryocyte progenitor cells requires the interplay of marrow stromal cells and polypeptide cytokines. Recently, characterization of c-Mpl, the receptor encoded by the proto-oncogene c-mpl, revealed structural homology with the haematopoietic cytokine receptor family, and its involvement in megakaryocyte development. We report here that the ligand for c-Mpl is relatively lineage specific, works both alone and synergistically with early acting cytokines to support megakaryocyte colony formation, and acts at a late stage of development to increase megakaryocyte size, polyploidization and expression of differentiation markers. In vivo, c-Mpl ligand stimulates platelet production by greatly expanding marrow and splenic megakaryocytes and their progenitors, and by shifting the distribution of megakaryocyte ploidy to higher values. Thus, as c-Mpl ligand has the expected characteristics of the major regulator of megakaryocyte development, we propose that it be termed thrombopoietin.

Journal ArticleDOI
01 Apr 1994-Ecology
TL;DR: Evaluating approaches to the conservation of rare and endangered plants and their impacts on threatened and endangered species in the wild is a good place to start.
Abstract: Schemske, D.W., B. C. Husband, M.H. Ruckelshaus, C. Goodwillie, I.M. Parker, and J.G. Bishop. 1994. Evaluating approaches to the conservation of rare and endangered plants. Ecology 75: 584-606.