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Showing papers by "University of British Columbia published in 2001"


Journal ArticleDOI
TL;DR: The revised criteria facilitate the diagnosis of MS in patients with a variety of presentations, including “monosymptomatic” disease suggestive of MS, disease with a typical relapsing‐remitting course, and disease with insidious progression, without clear attacks and remissions.
Abstract: The International Panel on MS Diagnosis presents revised diagnostic criteria for multiple sclerosis (MS). The focus remains on the objective demonstration of dissemination of lesions in both time and space. Magnetic resonance imaging is integrated with dinical and other paraclinical diagnostic methods. The revised criteria facilitate the diagnosis of MS in patients with a variety of presentations, including "monosymptomatic" disease suggestive of MS, disease with a typical relapsing-remitting course, and disease with insidious progression, without clear attacks and remissions. Previously used terms such as "clinically definite" and "probable MS" are no longer recommended. The outcome of a diagnostic evaluation is either MS, "possible MS" (for those at risk for MS, but for whom diagnostic evaluation is equivocal), or "not MS."

6,720 citations


Proceedings ArticleDOI
01 Sep 2001
TL;DR: This tutorial shows how to use AOP to implement crosscutting conerns in a concise modular way and includes a description of their underlying model, in terms of which a wide range of AOP languages can be understood.
Abstract: Aspect-oriented programming (AOP) is a technique for improving separation of concerns in software design and implementation. AOP works by providing explicit mechanisms for capturing the structure of crosscutting concerns. This tutorial shows how to use AOP to implement crosscutting conerns in a concise modular way. It works with AspectJ, a seamless aspect-oriented extension to the Java(tm) programming language, and with AspectC, an aspect-oriented extension to C in the style of AspectJ. It also includes a description of their underlying model, in terms of which a wide range of AOP languages can be understood.

3,187 citations


Journal Article
TL;DR: AspectJ as mentioned in this paper is a simple and practical aspect-oriented extension to Java with just a few new constructs, AspectJ provides support for modular implementation of a range of crosscutting concerns.
Abstract: Aspect] is a simple and practical aspect-oriented extension to Java With just a few new constructs, AspectJ provides support for modular implementation of a range of crosscutting concerns. In AspectJ's dynamic join point model, join points are well-defined points in the execution of the program; pointcuts are collections of join points; advice are special method-like constructs that can be attached to pointcuts; and aspects are modular units of crosscutting implementation, comprising pointcuts, advice, and ordinary Java member declarations. AspectJ code is compiled into standard Java bytecode. Simple extensions to existing Java development environments make it possible to browse the crosscutting structure of aspects in the same kind of way as one browses the inheritance structure of classes. Several examples show that AspectJ is powerful, and that programs written using it are easy to understand.

2,947 citations


Book ChapterDOI
18 Jun 2001
TL;DR: AspectJ provides support for modular implementation of a range of crosscutting concerns, and simple extensions to existing Java development environments make it possible to browse the crosscutting structure of aspects in the same kind of way as one browses the inheritance structure of classes.
Abstract: AspectJ? is a simple and practical aspect-oriented extension to Java?. With just a few new constructs, AspectJ provides support for modular implementation of a range of crosscutting concerns. In AspectJ's dynamic join point model, join points are well-defined points in the execution of the program; pointcuts are collections of join points; advice are special method-like constructs that can be attached to pointcuts; and aspects are modular units of crosscutting implementation, comprising pointcuts, advice, and ordinary Java member declarations. AspectJ code is compiled into standard Java bytecode. Simple extensions to existing Java development environments make it possible to browse the crosscutting structure of aspects in the same kind of way as one browses the inheritance structure of classes. Several examples show that AspectJ is powerful, and that programs written using it are easy to understand.

2,810 citations


Journal ArticleDOI
TL;DR: Simvastatin plus niacin provides marked clinical and angiographically measurable benefits in patients with coronary disease and low HDL levels, and the use of antioxidant vitamins in this setting must be questioned.
Abstract: Background Both lipid-modifying therapy and antioxidant vitamins are thought to have benefit in patients with coronary disease. We studied simvastatin–niacin and antioxidant-vitamin therapy, alone and together, for cardiovascular protection in patients with coronary disease and low plasma levels of high-density lipoprotein (HDL) cholesterol. Methods In a three-year, double-blind trial, 160 patients with coronary disease, low HDL cholesterol levels, and normal low-density lipoprotein (LDL) cholesterol levels were randomly assigned to receive one of four regimens: simvastatin plus niacin, antioxidants, simvastatin–niacin plus antioxidants, or placebos. The end points were arteriographic evidence of a change in coronary stenosis and the occurrence of a first cardiovascular event (death, myocardial infarction, stroke, or revascularization). Results The mean levels of LDL and HDL cholesterol were unaltered in the antioxidant group and the placebo group; these levels changed substantially (by –42 percent and +2...

1,918 citations


Journal ArticleDOI
TL;DR: The mechanisms that give rise to new species by divergent selection are reviewed, the alternatives are compared, recent tests in nature are summarized, and areas requiring research are highlighted.
Abstract: The ecological hypothesis of speciation is that reproductive isolation evolves ultimately as a consequence of divergent natural selection on traits between environments. Ecological speciation is general and might occur in allopatry or sympatry, involve many agents of natural selection, and result from a combination of adaptive processes. The main difficulty of the ecological hypothesis has been the scarcity of examples from nature, but several potential cases have recently emerged. I review the mechanisms that give rise to new species by divergent selection, compare ecological speciation with its alternatives, summarize recent tests in nature, and highlight areas requiring research.

1,820 citations


Journal ArticleDOI
05 Jan 2001-Science
TL;DR: The majority of parks are successful at stopping land clearing, and to a lesser degree effective at mitigating logging, hunting, fire, and grazing, suggesting that even modest increases in funding would directly increase the ability of parks to protect tropical biodiversity.
Abstract: We assessed the impacts of anthropogenic threats on 93 protected areas in 22 tropical countries to test the hypothesis that parks are an effective means to protect tropical biodiversity. We found that the majority of parks are successful at stopping land clearing, and to a lesser degree effective at mitigating logging, hunting, fire, and grazing. Park effectiveness correlates with basic management activities such as enforcement, boundary demarcation, and direct compensation to local communities, suggesting that even modest increases in funding would directly increase the ability of parks to protect tropical biodiversity.

1,531 citations


Journal ArticleDOI
Q. R. Ahmad1, R. C. Allen2, T. C. Andersen3, J. D. Anglin4  +202 moreInstitutions (17)
TL;DR: In this paper, the total flux of 8B neutrinos was determined to be (5.44±0.99)×106 cm−2 s−1, in close agreement with the predictions of solar models.
Abstract: Solar neutrinos from the decay of 8B have been detected at the Sudbury Neutrino Observatory (SNO) via the charged current (CC) reaction on deuterium and by the elastic scattering (ES) of electrons. The CC reaction is sensitive exclusively to νe, while the ES reaction also has a small sensitivity to νμ and ντ. The flux of νe from 8B decay measured by the CC reaction rate is φCC(ν e )=[1.75±0.07(stat.) −0.11 +0.12 (syst.)×0.05(theor.)]×106cm−2s−1. Assuming no flavor transformation, the flux inferred from the ES reaction rate is φES(ν x )=[2.39±0.34(stat.) −0.14 +0.16 (syst.)]×106cm−2s−1. Comparison of φCC(νe) to the Super-Kamiokande collaboration’s precision value of φES(νx) yields a 3.3σ difference, assuming the systematic uncertainties are normally distributed, providing evidence that there is a nonelectron flavor active neutrino component in the solar flux. The total flux of active 8B neutrinos is thus determined to be (5.44±0.99)×106 cm−2 s−1, in close agreement with the predictions of solar models.

1,514 citations


Journal ArticleDOI
20 Jul 2001-Science
TL;DR: It is demonstrated that wild-type huntingtin up-regulates transcription of brain-derived neurotrophic factor (BDNF), a pro-survival factor produced by cortical neurons that is necessary for survival of striatal neurons in the brain.
Abstract: Huntingtin is a 350-kilodalton protein of unknown function that is mutated in Huntington's disease (HD), a neurodegenerative disorder. The mutant protein is presumed to acquire a toxic gain of function that is detrimental to striatal neurons in the brain. However, loss of a beneficial activity of wild-type huntingtin may also cause the death of striatal neurons. Here we demonstrate that wild-type huntingtin up-regulates transcription of brain-derived neurotrophic factor (BDNF), a pro-survival factor produced by cortical neurons that is necessary for survival of striatal neurons in the brain. We show that this beneficial activity of huntingtin is lost when the protein becomes mutated, resulting in decreased production of cortical BDNF. This leads to insufficient neurotrophic support for striatal neurons, which then die. Restoring wild-type huntingtin activity and increasing BDNF production may be therapeutic approaches for treating HD.

1,321 citations


Journal ArticleDOI
TL;DR: The method of dynamic force spectroscopy (DFS) is being used to probe the complex relation between force-lifetime-and chemistry in single molecular bonds, and probes the inner world of molecular interactions to reveal barriers that are difficult or impossible to detect in assays of near equilibrium dissociation but that determine bond lifetime and strength under rapid detachment.
Abstract: On laboratory time scales, the energy landscape of a weak bond along a dissociation pathway is fully explored through Brownian-thermal excitations, and energy barriers become encoded in a dissociation time that varies with applied force. Probed with ramps of force over an enormous range of rates (force/time), this kinetic profile is transformed into a dynamic spectrum of bond rupture force as a function of loading rate. On a logarithmic scale in loading rate, the force spectrum provides an easy-to-read map of the prominent energy barriers traversed along the force-driven pathway and exposes the differences in energy between barriers. In this way, the method of dynamic force spectroscopy (DFS) is being used to probe the complex relation between force-lifetime-and chemistry in single molecular bonds. Most important, DFS probes the inner world of molecular interactions to reveal barriers that are difficult or impossible to detect in assays of near equilibrium dissociation but that determine bond lifetime and strength under rapid detachment. To use an ultrasensitive force probe as a spectroscopic tool, we need to understand the physics of bond dissociation under force, the impact of experimental technique on the measurement of detachment force (bond strength), the consequences of complex interactions in macromolecular bonds, and effects of multiply-bonded attachments.

1,288 citations


Journal ArticleDOI
TL;DR: The Canadian CT Head Rule is developed, a highly sensitive clinical decision rule for use of CT that has the potential to significantly standardise and improve the emergency management of patients with minor head injury.

Journal ArticleDOI
TL;DR: This paper is the first test of a parsimonious model that posits three factors as determinants of the adoption of electronic data interchange (EDI): readiness, perceived benefits, and external pressure.
Abstract: This paper is the first test of a parsimonious model that posits three factors as determinants of the adoption of electronic data interchange (EDI):readiness, perceived benefits, andexternal pressure. To construct the model, we identified and organized the factors that were found to be influential in prior EDI research. By testing all these factors together in one model, we are able to investigate their relative contributions to EDI adoption decisions. Senior purchasing managers, chosen for their experience with EDI and proximity to the EDI adoption decision, were surveyed and their responses analyzed using structural equation modeling. All three determinants were found to be significant predictors of intent to adopt EDI, with external pressure and readiness being considerably more important than perceived benefits. We show that the constructs in this model can be categorized into three levels:technological, organizational, andinterorganizational. We hypothesize that these categories of influence will also be determinants of the adoption of other emerging forms of interorganizational systems (IOS). 1

Journal ArticleDOI
TL;DR: There is a substantial and statistically significant increase in CHD and stroke in SLE that cannot be fully explained by traditional Framingham risk factors alone.
Abstract: Objective The frequency of coronary heart disease (CHD) and stroke are increased in systemic lupus erythematosus (SLE), but the extent of the increase is uncertain. We sought to determine to what extent the increase could not be explained by common risk factors. Methods The participants at two SLE registries were assessed retrospectively for the baseline level of the Framingham study risk factors and for the presence of vascular outcomes: nonfatal myocardial infarction (MI), death due to CHD, overall CHD (nonfatal MI, death due to CHD, angina pectoris, and congestive heart failure due to CHD), and stroke. For each patient, the probability of the given outcome was estimated based on the individual's risk profile and the Framingham multiple logistic regression model, corrected for observed followup. Ninety-five percent confidence intervals (95% CIs) were estimated by bootstrap techniques. Results Of 296 SLE patients, 33 with a vascular event prior to baseline were excluded. Of the 263 remaining patients, 34 had CHD events (17 nonfatal MIs, 12 CHD deaths) and 16 had strokes over a mean followup period of 8.6 years. After controlling for common risk factors at baseline, the increase in relative risk for these outcomes was 10.1 for nonfatal MI (95% CI 5.8–15.6), 17.0 for death due to CHD (95% CI 8.1–29.7), 7.5 for overall CHD (95% CI 5.1–10.4), and 7.9 for stroke (95% CI 4.0–13.6). Conclusion There is a substantial and statistically significant increase in CHD and stroke in SLE that cannot be fully explained by traditional Framingham risk factors alone.

Journal ArticleDOI
TL;DR: This paper examined the microfoundations of agglomeration economies for U.S. manufacturing industries using industries as observations, and regress the Ellison-Glaeser measure of spatial concentration on industry characteristics that proxy for the presence of knowledge spillovers, labor market pooling, input sharing, product shipping costs, and natural advantage.

Journal ArticleDOI
TL;DR: Evidence suggests that the presence of ADHD in children is associated to varying degrees with disturbances in family and marital functioning, disrupted parent–child relationships, specific patterns of parental cognitions about child behavior and reduced parenting self-efficacy, and increased levels of parenting stress and parental psychopathology.
Abstract: This review integrates and critically evaluates what is known about family characteristics associated with childhood Attention-Deficit/Hyperactivity Disorder (ADHD). Evidence suggests that the presence of ADHD in children is associated to varying degrees with disturbances in family and marital functioning, disrupted parent-child relationships, specific patterns of parental cognitions about child behavior and reduced parenting self-efficacy, and increased levels of parenting stress and parental psychopathology, particularly when ADHD is comorbid with conduct problems. However, the review reveals that little is known about the developmental mechanisms that underlie these associations, or the pathways through which child and family characteristics transact to exert their influences over time. In addition, the influence of factors such as gender, culture, and ADHD subtype on the association between ADHD and family factors remains largely unknown. We conclude with recommendations regarding the necessity for research that will inform a developmental psychopathology perspective of ADHD.

Journal ArticleDOI
TL;DR: The objective of this article is to review the cellular and molecular mechanisms that underlie the control of normal and neoplastic OSE cell growth, differentiation, and expression of indicators of neoplastics progression.
Abstract: The epithelial ovarian carcinomas, which make up more than 85% of human ovarian cancer, arise in the ovarian surface epithelium (OSE). The etiology and early events in the progression of these carcinomas are among the least understood of all major human malignancies because there are no appropriate animal models, and because methods to culture OSE have become available only recently. The objective of this article is to review the cellular and molecular mechanisms that underlie the control of normal and neoplastic OSE cell growth, differentiation, and expression of indicators of neoplastic progression. We begin with a brief discussion of the development of OSE, from embryonic to the adult. The pathological and genetic changes of OSE during neoplastic progression are next summarized. The histological characteristics of OSE cells in culture are also described. Finally, the potential involvement of hormones, growth factors, and cytokines is discussed in terms of their contribution to our understanding of the physiology of normal OSE and ovarian cancer development.

Journal ArticleDOI
TL;DR: In this paper, a new division of landslide materials is proposed, based on genetic and morphological aspects rather than arbitrary grain-size limits, which would allow the terms to be retained with their original meanings while making their application less ambiguous.
Abstract: As a result of the widespread use of the landslide classifications of Varnes (1978), and Hutchinson (1988), certain terms describing common types of flow-like mass movements have become entrenched in the language of engineering geology. Example terms include debris flow, debris avalanche and mudslide. Here, more precise definitions of the terms are proposed, which would allow the terms to be retained with their original meanings while making their application less ambiguous. A new division of landslide materials is proposed, based on genetic and morphological aspects rather than arbitrary grain-size limits. The basic material groups include sorted materials: gravel, sand, silt, and clay, unsorted materials: debris, earth and mud, peat and rock. Definitions are proposed for relatively slow non-liquefied sand or gravel flows, extremely rapid sand, silt or debris flow slides accompanied by liquefaction, clay flow slides involving extra-sensitive clays, peat flows, slow to rapid earth flows in nonsensitive plastic clays, debris flows which occur in steep established channels or gullies, mud flows considered as cohesive debris flows, debris floods involving massive sediment transport at limited discharges, debris avalanches which occur on open hill slopes and rock avalanches formed by large scale failures of bedrock.

Journal ArticleDOI
TL;DR: Prevention by avoidance of undercooked meat or seafood, avoidance of unpasteurized milk or soft cheese, and selected use of available typhoid vaccines for travelers to areas where typhoid is endemic are key to the control of infectious diarrhea.
Abstract: The widening array of recognized enteric pathogens and the increasing demand for cost-containment sharpen the need for careful clinical and public health guidelines based on the best evidence currently available. Adequate fluid and electrolyte replacement and maintenance are key to managing diarrheal illnesses. Thorough clinical and epidemiological evaluation must define the severity and type of illness (e.g., febrile, hemorrhagic, nosocomial, persistent, or inflammatory), exposures (e.g., travel, ingestion of raw or undercooked meat, seafood, or milk products, contacts who are ill, day care or institutional exposure, recent antibiotic use), and whether the patient is immunocompromised, in order to direct the performance of selective diagnostic cultures, toxin testing, parasite studies, and the administration of antimicrobial therapy (the latter as for traveler's diarrhea, shigellosis, and possibly Campylobacter jejuni enteritis). Increasing numbers of isolates resistant to antimicrobial agents and the risk of worsened illness (such as hemolytic uremic syndrome with Shiga toxin-producing Escherichia coli O157:H7) further complicate antimicrobial and antimotility drug use. Thus, prevention by avoidance of undercooked meat or seafood, avoidance of unpasteurized milk or soft cheese, and selected use of available typhoid vaccines for travelers to areas where typhoid is endemic are key to the control of infectious diarrhea.

Journal ArticleDOI
TL;DR: Cationic peptides seem to have effector functions in innate immunity and can upregulate the expression of multiple genes in eukaryotic cells and involve the dampening of signalling by bacterial molecules such as lipopolysaccharide and lipoteichoic acid.
Abstract: Summary Cationic antimicrobial peptides are produced by all organisms, from plants and insects to human beings, as a major part of their immediately effective, nonspecific defences against infections. With the increasing development of antibiotic resistance among key bacterial pathogens, there is an urgent need to discover novel classes of antibiotics. Therefore, cationic peptides are being developed through clinical trials as anti-infective agents. In addition to their ability to kill microbes, these peptides seem to have effect or functions in innate immunity and can upregulate the expression of multiplegenes in eukaryotic cells. One such function might involve the dampening of signalling by bacterial molecules such as lipopolysaccharide and lipoteichoic acid.

Journal ArticleDOI
TL;DR: Values of AIP correspond closely to those of FER(HDL) and to lipoprotein particle size and thus could be used as a marker of plasma atherogenicity.

Journal ArticleDOI
10 Aug 2001-Science
TL;DR: In vivo evidence is provided for substantial release of endogenous dopamine in the striatum of PD patients in response to placebo, indicating that the placebo effect in PD is powerful and is mediated through activation of the damaged nigrostriatal dopamine system.
Abstract: The power of placebos has long been recognized for improving numerous medical conditions such as Parkinson's disease (PD). Little is known, however, about the mechanism underlying the placebo effect. Using the ability of endogenous dopamine to compete for [11C]raclopride binding as measured by positron emission tomography, we provide in vivo evidence for substantial release of endogenous dopamine in the striatum of PD patients in response to placebo. Our findings indicate that the placebo effect in PD is powerful and is mediated through activation of the damaged nigrostriatal dopamine system.

Journal ArticleDOI
John Douglas Mcpherson1, Marco A. Marra2, Marco A. Marra1, LaDeana W. Hillier1, Robert H. Waterston1, Asif T. Chinwalla1, John W. Wallis1, Mandeep Sekhon1, Kristine M. Wylie1, Elaine R. Mardis1, Richard K. Wilson1, Robert S. Fulton1, Tamara A. Kucaba1, Caryn Wagner-McPherson1, William B. Barbazuk1, Simon G. Gregory3, Sean Humphray3, Lisa French3, R Evans3, Graeme Bethel3, Adam Whittaker3, Jane L. Holden3, Owen T. McCann3, Andrew Dunham3, Carol Soderlund4, Carol Scott3, David R. Bentley3, Gregory D. Schuler5, Hsiu Chuan Chen5, Wonhee Jang5, Eric D. Green5, Jacquelyn R. Idol5, Valerie Maduro5, Kate Montgomery6, Eunice Lee6, Ashley Miller6, Suzanne Emerling6, Raju Kucherlapati6, Richard A. Gibbs7, Steve Scherer7, J. Harley Gorrell7, Erica Sodergren7, Kerstin P. Clerc-Blankenburg7, Paul E. Tabor7, S. Naylor8, Dawn Garcia8, J. de Jong9, J. de Jong10, J. de Jong11, Joseph J. Catanese10, Joseph J. Catanese9, Joseph J. Catanese11, Norma J. Nowak9, Kazutoyo Osoegawa9, Kazutoyo Osoegawa10, Kazutoyo Osoegawa11, Shizhen Qin12, Lee Rowen12, Anuradha Madan12, Monica Dors12, Leroy Hood12, Barbara J. Trask13, Cynthia Friedman13, Hillary Massa13, Vivian G. Cheung14, Ilan R. Kirsch5, Thomas Reid5, Raluca Yonescu5, Jean Weissenbach, Thomas Brüls, Roland Heilig, Elbert Branscomb15, Anne S. Olsen15, Norman A. Doggett15, Jan Fang Cheng15, Trevor Hawkins15, Richard M. Myers16, Jin Shang16, Lucía Ramírez16, Jeremy Schmutz16, Olivia Velasquez16, Kami Dixon16, Nancy E. Stone16, David R. Cox16, David Haussler17, W. James Kent17, Terrence S. Furey17, Sanja Rogic17, Scot Kennedy17, Steven J.M. Jones2, André Rosenthal5, Gaiping Wen5, Markus Schilhabel5, Gernot Gloeckner5, Gerald Nyakatura5, Reiner Siebert18, Brigitte Schlegelberger18, Julie R. Korenberg19, Xiao Ning Chen19, Asao Fujiyama, Masahira Hattori, Atsushi Toyoda, Tetsushi Yada, Hong Seok Park, Yoshiyuki Sakaki, Nobuyoshi Shimizu20, Shuichi Asakawa20, Kazuhiko Kawasaki20, Takashi Sasaki20, Ai Shintani20, Atsushi Shimizu20, Kazunori Shibuya20, Jun Kudoh20, Shinsei Minoshima20, Juliane Ramser21, Peter Seranski21, Céline Hoff21, Annemarie Poustka21, Richard Reinhardt21, Hans Lehrach21 
15 Feb 2001-Nature
TL;DR: The construction of the whole-genome bacterial artificial chromosome (BAC) map and its integration with previous landmark maps and information from mapping efforts focused on specific chromosomal regions are reported.
Abstract: The human genome is by far the largest genome to be sequenced, and its size and complexity present many challenges for sequence assembly. The International Human Genome Sequencing Consortium constructed a map of the whole genome to enable the selection of clones for sequencing and for the accurate assembly of the genome sequence. Here we report the construction of the whole-genome bacterial artificial chromosome (BAC) map and its integration with previous landmark maps and information from mapping efforts focused on specific chromosomal regions. We also describe the integration of sequence data with the map.

Journal ArticleDOI
TL;DR: In this paper, the authors explore the effect of exclusionary ethical investing on corporate behavior in a risk-averse, equilibrium setting and show that it leads to polluting firms being held by fewer investors since green investors eschew polluting stocks.
Abstract: This paper explores the effect of exclusionary ethical investing on corporate behavior in a risk-averse, equilibrium setting. While arguments exist that ethical investing can influence a firm's cost of capital, and so affect investment, no equilibrium model has been presented to do so. We show that exclusionary ethical investing leads to polluting firms being held by fewer investors since green investors eschew polluting firms' stock. This lack of risk sharing among non-green investors leads to lower stock prices for polluting firms, thus raising their cost of capital. If the higher cost of capital more than overcomes a cost of reforming (i.e., a polluting firm cleaning up its activities), then polluting firms will become socially responsible because of exclusionary ethical investing. A key determinant of the incentive for polluting firms to reform is the fraction of funds controlled by green investors. In our model, empirically reasonable parameter estimates indicate, that more than 20 % green investors are required to induce any polluting firmss to reform. Existing empirical evidence indicates that at most 10% of funds are invested by green investors.

Journal ArticleDOI
TL;DR: In this paper, two intense dust storms were generated over the Gobi desert by springtime low-pressure systems descending from the northwest, and the windblown dust was detected and its evolution followed by its yellow color on SeaWiFS satellite images, routine surface-based monitoring and through serendipitous observations.
Abstract: On April 15 and 19, 1998, two intense dust storms were generated over the Gobi desert by springtime low-pressure systems descending from the northwest. The windblown dust was detected and its evolution followed by its yellow color on SeaWiFS satellite images, routine surface-based monitoring, and through serendipitous observations. The April 15 dust cloud was recirculating, and it was removed by a precipitating weather system over east Asia. The April 19 dust cloud crossed the Pacific Ocean in 5 days, subsided to the surface along the mountain ranges between British Columbia and California, and impacted severely the optical and the concentration environments of the region. In east Asia the dust clouds increased the albedo over the cloudless ocean and land by up to 10–20%, but it reduced the near-UV cloud reflectance, causing a yellow coloration of all surfaces. The yellow colored backscattering by the dust eludes a plausible explanation using simple Mie theory with constant refractive index. Over the West Coast the dust layer has increased the spectrally uniform optical depth to about 0.4, reduced the direct solar radiation by 30–40%, doubled the diffuse radiation, and caused a whitish discoloration of the blue sky. On April 29 the average excess surface-level dust aerosol concentration over the valleys of the West Coast was about 20–50 μg/m3 with local peaks >100 μg/m3. The dust mass mean diameter was 2–3 μm, and the dust chemical fingerprints were evident throughout the West Coast and extended to Minnesota. The April 1998 dust event has impacted the surface aerosol concentration 2–4 times more than any other dust event since 1988. The dust events were observed and interpreted by an ad hoc international web-based virtual community. It would be useful to set up a community-supported web-based infrastructure to monitor the global aerosol pattern for such extreme aerosol events, to alert and to inform the interested communities, and to facilitate collaborative analysis for improved air quality and disaster management.

Journal ArticleDOI
28 Nov 2001-JAMA
TL;DR: The data demonstrate uniformly low rates of disease progression to death and AIDS or death among patients starting antiretroviral therapy with CD4 cell counts of at least 200/microL, as well as a prior diagnosis of acquired immunodeficiency syndrome (AIDS).
Abstract: ContextCurrent recommendations for initiation of antiretroviral therapy in patients infected with human immunodeficiency virus type 1 (HIV) are based on CD4 T-lymphocyte cell counts and plasma HIV RNA levels. The relative prognostic value of each marker following initiation of therapy has not been fully characterized.ObjectiveTo describe rates of disease progression to death and AIDS or death among patients starting triple-drug antiretroviral therapy, stratified by baseline CD4 cell count and HIV RNA levels.Design, Setting, and ParticipantsPopulation-based analysis of 1219 antiretroviral therapy–naive HIV-positive men and women aged 18 years or older in British Columbia who initiated triple-drug therapy between August 1, 1996, and September 30, 1999.Main Outcome MeasureCumulative mortality rates from the initiation of triple-drug antiretroviral therapy to September 30, 2000, determined using various CD4 cell and plasma HIV RNA thresholds.ResultsAs of September 30, 2000, 82 patients had died of AIDS-related causes, for a crude AIDS-related mortality rate of 6.7%. The product limit estimate (SE) of the cumulative mortality rate at 12 months was 2.9% (0.5%). In univariate analyses, a prior diagnosis of acquired immunodeficiency syndrome (AIDS), CD4 cell count, use of protease inhibitors, and HIV RNA level were associated with mortality. There was no difference in mortality by age or sex. Only CD4 cell count remained statistically significant in the multivariate analysis. After controlling for AIDS, protease inhibitor use, and plasma HIV RNA level at baseline, patients with CD4 cell counts of less than 50/µL were 6.67 (95% confidence interval [CI], 3.61-12.34) times and those with counts of 50/µL to 199/µL were 3.41 (95% CI, 1.93-6.03) times more likely to die than those with counts of at least 200/µL.ConclusionOur data demonstrate uniformly low rates of disease progression to death and AIDS or death among patients starting antiretroviral therapy with CD4 cell counts of at least 200/µL. In our study, disease progression to death and AIDS or death was clustered among patients starting therapy with CD4 cell counts less than 200/µL.

Journal ArticleDOI
TL;DR: For instance, this article found that criminal psychopaths showed significantly less affect-related activity in the amygdala/hippocampal formation, parahippocampa gyrus, ventral striatum, and anterior and posterior cingulate gyri compared with nonpsychopaths and noncriminal control participants.

Journal ArticleDOI
TL;DR: The first article in this series will comprehensively review the pathophysiology of SCI while emphasizing those mechanisms for which pharmacologic therapy has been developed, and the second article reviews the pharmacologic interventions for SCI.
Abstract: Spinal cord injury (SCI) is a devastating and common neurologic disorder that has profound influences on modern society from physical, psychosocial, and socioeconomic perspectives. Accordingly, the present decade has been labeled the Decade of the Spine to emphasize the importance of SCI and other spinal disorders. Spinal cord injury may be divided into both primary and secondary mechanisms of injury. The primary injury, in large part, determines a given patient's neurologic grade on admission and thereby is the strongest prognostic indicator. However, secondary mechanisms of injury can exacerbate damage and limit restorative processes, and hence, contribute to overall morbidity and mortality. A burgeoning body of evidence has facilitated our understanding of these secondary mechanisms of injury that are amenable to pharmacological interventions, unlike the primary injury itself. Secondary mechanisms of injury encompass an array of perturbances and include neurogenic shock, vascular insults such as hemorrhage and ischemia-reperfusion, excitotoxicity, calcium-mediated secondary injury and fluid-electrolyte disturbances, immunologic injury, apoptosis, disturbances in mitochondrion function, and other miscellaneous processes. Comprehension of secondary mechanisms of injury serves as a basis for the development and application of targeted pharmacological strategies to confer neuroprotection and restoration while mitigating ongoing neural injury. The first article in this series will comprehensively review the pathophysiology of SCI while emphasizing those mechanisms for which pharmacologic therapy has been developed, and the second article reviews the pharmacologic interventions for SCI.

Journal ArticleDOI
29 Nov 2001-Nature
TL;DR: It is shown that misreporting by countries with large fisheries, combined with the large and widely fluctuating catch of species such as the Peruvian anchoveta, can cause globally spurious trends and influence unwise investment decisions by firms in the fishing sector and by banks, and prevent the effective management of international fisheries.
Abstract: Over 75% of the world marine fisheries catch (over 80 million tonnes per year) is sold on international markets, in contrast to other food commodities (such as rice). At present, only one institution, the Food and Agriculture Organization of the United Nations (FAO) maintains global fisheries statistics. As an intergovernmental organization, however, FAO must generally rely on the statistics provided by member countries, even if it is doubtful that these correspond to reality. Here we show that misreporting by countries with large fisheries, combined with the large and widely fluctuating catch of species such as the Peruvian anchoveta, can cause globally spurious trends. Such trends influence unwise investment decisions by firms in the fishing sector and by banks, and prevent the effective management of international fisheries.

Journal ArticleDOI
TL;DR: Results show that a range of different particles stimulate alveolar macrophages to produce proinflammatory cytokines and these cytokines are also present in the blood of subjects during an episode of acute atmospheric air pollution.
Abstract: Elevated levels of ambient particulate matter (PM(10)) have been associated with increased cardiopulmonary morbidity and mortality. We previously showed that the deposition of particles in the lung induces a systemic inflammatory response that includes stimulation of the bone marrow. This marrow response is related to mediators released by alveolar macrophages (AM) and in this study we measured cytokines produced by human AM exposed to ambient particles of different composition and size. Identified cytokines were also measured in the circulation of healthy young subjects exposed to air pollutants during the 1997 Southeast Asian forest fires. Human AM were incubated with particle suspensions of residual oil fly ash (ROFA), ambient urban particles (EHC 93), inert carbon particles, and latex particles of different sizes (0.1, 1, and 10 microm) and concentrations for 24 h. Tumor necrosis factor-alpha (TNF-alpha) increases in a dose-dependent manner when AM were exposed to EHC 93 particles (p < 0.02). The TNF response of AM exposed to different sizes of latex particles was similar. The latex (158 +/- 31%), inert carbon (179 +/- 32%), and ROFA (216 +/- 34%) particles all show a similar maximum TNF response (percent change from baseline) whereas EHC 93 (1,020 +/- 212%, p < 0.05) showed a greater maximum response that was similar to lipopolysaccharide (LPS) 1 microg/ml (812 +/- 320%). Macrophages incubated with an optimal dose of EHC 93 particles (0.1 mg/ml) also produce a broad spectrum of other proinflammatory cytokines, particularly interleukin (IL)-6 (p < 0.01), IL-1 beta (p < 0.05), macrophage inflammatory protein-1 alpha (MIP-1 alpha) (p < 0.05), and granulocyte macrophage colony-stimulating factor (GM-CSF) (p < 0.01) with no difference in concentrations of the anti-inflammatory cytokine IL-10 (p = NS). Circulating levels of IL-1 beta, IL-6, and GM-CSF were elevated in subjects exposed to high levels of PM(10) during an episode of acute air pollution. These results show that a range of different particles stimulate AM to produce proinflammatory cytokines and these cytokines are also present in the blood of subjects during an episode of acute atmospheric air pollution. We postulate that these cytokines induced a systemic response that has an important role in the pathogenesis of the cardiopulmonary adverse health effects associated with atmospheric pollution.

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TL;DR: The N-terminal processing of the CXC chemokines stromal cell-derived factor (SDF)-1α and β by MMP-2 is reported, suggesting that MMPs may be important regulatory proteases in attenuating SDF-1 function and point to a deep convergence of two important networks, chemokine and M MPs, to regulate leukocytic activity in vivo.