bluuebunny/crossref_metadata_2025 huggingface dataset:
ICSBP Is Essential for the Development of Mouse Type I Interferon-producing Cells and for the Generation and Activation of CD8α+ Dendritic Cells
Authors: Schiavoni Giovanna , Mattei Fabrizio , Sestili Paola , Borghi Paola , Venditti Massimo , Morse Herbert C. , Belardelli Filippo , Gabriele Lucia
Published: December 2002

Interferon (IFN) consensus sequence-binding protein (ICSBP) is a transcription factor playing a critical role in the regulation of lineage commitment, especially in myeloid cell differentiation. In this study, we have characterized the phenotype and activation pattern of subsets of dendritic cells (DCs) in ICSBP−/− mice. Remarkably, the recently identified mouse IFN-producing cells (mIPCs) were absent in all lymphoid organs from ICSBP−/− mice, as revealed by lack of CD11clowB220+Ly6C+CD11b− cells. In parallel, CD11c+ cells isolated from ICSBP−/− spleens were unable to produce type I IFNs in response to viral stimulation. ICSBP−/− mice also displayed a marked reduction of the DC subset expressing the CD8α marker (CD8α+ DCs) in spleen, lymph nodes, and thymus. Moreover, ICSBP−/− CD8α+ DCs exhibited a markedly impaired phenotype when compared with WT DCs. They expressed very low levels of costimulatory molecules (intercellular adhesion molecule [ICAM]-1, CD40, CD80, CD86) and of the T cell area-homing chemokine receptor CCR7, whereas they showed higher levels of CCR2 and CCR6, as revealed by reverse transcription PCR. In addition, these cells were unable to undergo full phenotypic activation upon in vitro culture in presence of maturation stimuli such as lipopolysaccharide or poly (I:C), which paralleled with lack of Toll-like receptor (TLR)3 mRNA expression. Finally, cytokine expression pattern was also altered in ICSBP−/− DCs, as they did not express interleukin (IL)-12p40 or IL-15, but they displayed detectable IL-4 mRNA levels. On the whole, these results indicate that ICSBP is a crucial factor in the regulation of two possibly linked processes: (a) the development and activity of mIPCs, whose lack in ICSBP−/− mice may explain their high susceptibility to virus infections; (b) the generation and activation of CD8α+ DCs, whose impairment in ICSBP−/− mice can be responsible for the defective generation of a Th1 type of immune response.
Geometric Insight Into the Dynamics of a Rigid Body Using the Spatial Triangle of Screws
Authors: Pennock Gordon R. , Meehan Patrick J.
Published: December 2002

Geometric relationships between the velocity screw and momentum screw are presented, and the dual angle between these two screws is shown to provide important insight into the kinetics of a rigid body. Then the centripetal screw is defined, and the significance of this screw in a study of the dynamics of a rigid body is explained. The dual-Euler equation, which is the dual form of the Newton-Euler equations of motion, is shown to be a spatial triangle. The vertices of the triangle are the centripetal screw, the time rate of change of momentum screw, and the force screw. The sides of the triangles are three dual angles between the three vertices. The spatial triangle provides valuable geometrical insight into the dynamics of a rigid body and is believed to be a meaningful alternative to existing analytical techniques. The authors believe that the work presented in this paper will prove useful in a dynamic analysis of closed-loop spatial mechanisms and multi-rigid body open-chain systems.
Initial Estimates in the Design of Central-Lever Steering Linkages
Authors: Simionescu P. A. , Smith M. R.
Published: December 2002

Parametric design charts are proposed for the central-lever steering linkage, generated for simplified reference configuration mechanisms, the geometry of which is defined by only four parameters. This highlights the fact, yet not generally acknowledged, that the steering law ensured by a mechanism with adjacent central joints (known as bell crank mechanism), can be identically generated by a triple central joint variant of the same. Particular configurations are identified in which the length of the central lever does not affect the wheel-to-wheel transmission function of the mechanism, permitting a simplified synthesis for the cases in which the maximum stroke of the input member is imposed as a design specification.
Surface Temperature Calculation and its Application to Surface Fatigue Strength Evaluation
Authors: Deng Gang , Nakanishi Tsutomu , Kato Masana
Published: December 2002

In recent years, power transmission gears for vehicles run at higher speeds and loads and are accompanied by very high surface temperatures. Under such a high surface temperature condition, the surface strength cannot be evaluated correctly only by the use of Hertzian stress. This research attempts to introduce a new surface strength evaluation method considering the surface temperature rise. First, the surface temperatures of rollers under different rolling and sliding conditions are measured using a thermocouple. The effects of load P, mean tangential velocity Vm and sliding velocity Vs on surface temperature are investigated and analyzed. Then, an experimental equation is presented which shows the linear relationship between surface temperature and GRP0.86Vs1.31Vm−0.83 value. Based on the comparisons between calculated and measured tooth surface temperatures, this equation is confirmed applicable to gear tooth surface temperature evaluation as well. A surface temperature index is proposed for surface strength evaluation. The relationship between the surface temperature index and the number of load cycles of the rollers is investigated. The results indicate the possibility to evaluate the surface strength based on the surface temperature.
Enumeration of 1-DOF Planetary Gear Train Graphs Based on Functional Constraints
Authors: del Castillo Jose M.
Published: December 2002

A procedure for the enumeration of the graphs of 1-dof planetary gear trains is presented. The planetary gear trains enumerated have a single input shaft and a single output shaft. These gear trains should satisfy certain functional constraints that avoid the existence of idle links. These constraints are derived. The enumeration of the graphs exploits the resulting particular features of the structure of planetary gear trains by proceeding gradually through different levels of that structure. The procedure includes a check for isomorphism among the resulting graphs. Finally, the graphs of the planetary gear trains having up to 9 links are presented. Those graphs containing embedded structures are identified.
Design of One Stage Planetary Gear Train With Improved Conditions of Load Distribution and Reduced Transmission Errors
Authors: Litvin F. L. , Vecchiato D. , Demenego A. , Karedes E. , Hansen B. , Handschuh R.
Published: December 2002

The authors propose an approach for the design of one-stage planetary gear train with reduced transmission errors, localized bearing contact and improved conditions of distribution of load between the planetary gears. The planetary gear train is considered as a multi-body mechanical system of rigid bodies. The proposed approach is based: (i) on modification of geometry of gear tooth surfaces, and (ii) minimization and equalization of the backlash between the contacting gear tooth surfaces. The modification of geometry is accomplished: (i) by double-crowning of planetary gears, and (ii) by application of screw involute surfaces of the same direction of screws for the sun and the ring gears. The proposed geometry enables: (i) predesign of parabolic function of transmission errors for reduction of noise and vibration, and (ii) a simple method of regulation and equalization of the backlash between the gear tooth.
Integrated Real-Time Calibration of Electromagnetic Tracking of User Motions for Engineering Applications in Virtual Environments
Authors: Jayaram Uma , Repp Roglenda
Published: December 2002

A real-time integrated calibration system for virtual reality environments has been developed that enables accurate electromagnetic tracking of user motions. Electromagnetic tracking systems suffer degradation in accuracy due to the presence of metals and other electromagnetic distortions in the environment. Calibration of the virtual environment to account for these distortions is essential for VR applications in engineering where correlation between the virtual environment and the physical world is important. The major contribution of the paper is the presentation of a comprehensive methodology for calibrating the VR space, the numerical/mathematical techniques proposed for the calibration, and case studies for calibration accuracy and execution time to enable using these techniques in real time in an integrated setup.
Decomposition-Based Assembly Synthesis Based on Structural Considerations
Authors: Yetis F. A. , Saitou K.
Published: December 2002

This paper presents a method for decomposition of structural products in order to provide the product designer with choices for feasible assemblies. The synthesis of assemblies is done by decomposing a complex structure obtained via structural topology optimization into an assembly of multiple structural members with simpler geometries. The aim is at providing a systematic approach to explore a large number of decompositions prior to the detailed component design phase. Initially, the structure, which is represented as a bitmap image, is transformed to a graph with equivalent topology through application of image processing algorithms. Then, the obtained graph is decomposed by a genetic algorithm into subgraphs using stiffness-based criteria. Results for an example structure are given to clarify and discuss the method.
Stabilization of Baumgarte’s Method Using the Runge-Kutta Approach
Authors: Lin Shih-Tin , Huang Jiann-Nan
Published: December 2002

The dynamic equations of motion of the constrained multibody mechanical system are mixed differential-algebraic equations (DAE). The DAE systems cannot be solved using numerical integration methods that are commonly used for solving ordinary differential equations. To solve this problem, Baumgarte proposed a constraint stabilization method in which a position and velocity terms were added in the second derivative of the constraint equation. The disadvantage of this method is that there is no reliable method for selecting the coefficients of the position and velocity terms. Improper selection of these coefficients can lead to erroneous results. In this study, stability analysis methods in digital control theory are used to solve this problem. Correct choice of the coefficients for the Runge-Kutta method is found.
Role of individual and contextual effects in injury mortality: new evidence from small area analysis
Authors: Borrell C , Rodríguez M , Ferrando J , Brugal M T , Pasarín M I , Martínez V , Plaséncia A
Published: December 2002

Objective:To analyse the role of individual and contextual variables in injury mortality inequalities from a small area analysis perspective, looking at the data for the city of Barcelona (Spain) for 1992–98.

Setting:Barcelona (Spain).

Methods:All injury deaths in residents older than 19, which occurred in the period 1992–98 were included (n=4393). Age and sex specific mortality rates were calculated for each educational level and each cause of death (traffic injuries, falls, drug overdose, suicide, other injuries). The contextual variables included were the proportion of men unemployed, and the proportion of men in jail, in each neighbourhood. Multilevel Poisson regression models were fitted using data grouped by age, educational level, and neighbourhood for each sex.

Results:Death rates were higher in males, at the extremes of the age distribution (under 44 and over 74 years), and for lower educational levels. The results of the Poisson multilevel models indicate that inequalities by educational level follow a gradient, with higher risks for the population with no schooling, after having adjusted for the contextual variables of the neighbourhood. Such inequalities were more important in the youngest age group (20–34 years), as relative risk of 5.41 (95% confidence interval (CI) 3.9 to 7.4) for all injury causes in males and 4.38 (95% CI 2.3 to 8.4) in females. The highest relative risks were found for drug overdose. There was a contextual neighbourhood effect (the higher the deprivation, the higher the mortality) after having taken into account individual variables.

Conclusion:The findings underscore the need to implement injury prevention strategies not only at the individual level taking into account socioeconomic position, but also at the neighbourhood level.
Effect of helmet wear on the incidence of head/face and cervical spine injuries in young skiers and snowboarders
Authors: Macnab A J , Smith T , Gagnon F A , Macnab M
Published: December 2002

Purpose:To evaluate whether helmets increase the incidence and/or severity of cervical spine injury; decrease the incidence of head injury; and/or increase the incidence of collisions (as a reflection of adverse effects on peripheral vision and/or auditory acuity) among young skiers and snowboarders.

Methods:During one ski season (1998–99) at a world class ski resort, all young skiers and snowboarders (<13 years of age) presenting with head, face, or neck injury to the one central medical facility at the base of the mountain were identified. On presentation to the clinic, subjects or their parents completed a questionnaire reviewing their use of helmets and circumstances surrounding the injury event. Physicians documented the site and severity of injury, investigations, and disposition of each patient. Concurrently, counts were made at the entry to the ski area of the number of skiers and snowboarders wearing helmets.

Results:Seventy children were evaluated at the clinic following ski/snowboard related head, neck, and face injuries. Fourteen did not require investigation or treatment. Of the remaining 56, 17 (30%) were wearing helmets and 39 (70%) were not. No serious neck injury occurred in either group. Using helmet-use data from the hill, among those under 13 years of age, failure to wear a helmet increased the risk of head, neck, or face injury (relative risk (RR) 2.24, 95% confidence interval (CI) 1.23 to 4.12). When corrected for activity, RR was 1.77 and 95% CI 0.98 to 3.19. There was no significant difference in the odds ratio for collisions. The two groups may have been different in terms of various relevant characteristics not evaluated. No separate analysis of catastrophic injuries was possible.

Conclusion:This study suggests that, in skiers and snowboarders under 13 years of age, helmet use does not increase the incidence of cervical spine injury and does reduce the incidence of head injury requiring investigation and/or treatment.
POPULATION-LEVELEFFECTS OFPESTICIDES ANDOTHERTOXICANTS ONARTHROPODS
Authors: Stark John D. , Banks John E.
Published: December 2002

▪ Abstract  New developments in ecotoxicology are changing the way pesticides and other toxicants are evaluated. An emphasis on life histories and population fitness through the use of demography, other measures of population growth rate, field studies, and modeling are being exploited to derive better estimates of pesticide impacts on both target and nontarget species than traditional lethal dose estimates. We review the state of the art in demographic toxicology, an approach to the evaluation of toxicity that uses life history parameters and other measures of population growth rate. A review of the literature revealed that 75 studies on the use of demography and similar measures of population growth rate in toxicology have been published since 1962. Of these 75 studies, the majority involved arthropods. Recent evaluations have indicated that ecotoxicological analysis based on population growth rate results in more accurate assessments of the impacts of pesticides and other toxicants because measures of population growth rate combine lethal and sublethal effects, which lethal dose/concentration estimates (LD/LC50) cannot do. We contend that to advance our knowledge of toxicant impacts on arthropods, the population growth rate approach should be widely adopted.
BIOCHEMISTRY AND MOLECULAR BIOLOGY OF DE NOVO ISOPRENOID PHEROMONE PRODUCTION IN THE SCOLYTIDAE
Authors: Seybold Steven J. , Tittiger Claus
Published: December 2002

▪ Abstract  Recent application of biochemical and molecular techniques to study the genesis of scolytid aggregation pheromones has revealed that bark beetles are primarily responsible for the endogenous synthesis of widely occurring pheromone components such as ipsenol, ipsdienol, and frontalin. Because many of the chemical signals are isoprenoids, the roles of the mevalonate biosynthetic pathway and the enzyme HMG-CoA reductase (HMG-R) have been investigated. This has led to the identification of endothelial cells in the anterior midgut as the site of synthesis and to the concept that de novo pheromone biosynthesis is regulated in part by the positive effect of juvenile hormone III (JHIII) on gene expression for HMG-R. Both the pronounced regulation by JHIII and the expression pattern of eukaryotic HMG-R argue against synthesis of these pheromones by prokaryotes. As the mevalonate pathway and its regulation have been studied in few other insects, broader issues addressed through the study of scolytid pheromone biosynthesis include major step versus coordinate regulation of the pathway and a genomics approach to elucidating the entire pathway and the mode of action of JHIII.
Male Accessory Gland Secretions: Modulators of Female Reproductive Physiology and Behavior
Authors: Gillott Cedric
Published: December 2002

Secretions of male accessory glands contain a variety of bioactive molecules. When transferred during mating, these molecules exert wide-ranging effects on female reproductive activity and they improve the male's chances of siring a significant proportion of the female's offspring. The accessory gland secretions may affect virtually all aspects of the female's reproductive activity. The secretions may render her unwilling or unable to remate for some time, facilitating sperm storage and ensuring that any eggs laid will be fertilized by that male's sperm. They may stimulate an increase in the number and rate of development of eggs and modulate ovulation and/or oviposition. Antimicrobial agents in the secretions ensure that the female reproductive tract is a hospitable environment during sperm transfer. In a few species the secretions include noxious chemicals. These are sequestered by developing eggs that are thereby protected from predators and pathogens when laid.
BELOWGROUNDHERBIVORY BYINSECTS: Influence on Plants and Aboveground Herbivores
Authors: Blossey Bernd , Hunt-Joshi Tamaru R.
Published: December 2002

▪ Abstract  Investigations of plant-herbivore interactions continue to be popular; however, a bias neglecting root feeders may limit our ability to understand how herbivores shape plant life histories. Root feeders can cause dramatic plant population declines, often associated with secondary stress factors such as drought or grazing. These severe impacts resulted in substantial interest in root feeders as agricultural pests and increasingly as biological weed control agents, particularly in North America. Despite logistical difficulties, establishment rates in biocontrol programs are equal or exceed those of aboveground herbivores (67.2% for aboveground herbivores, 77.5% for belowground herbivores) and root feeders are more likely to contribute to control (53.7% versus 33.6%). Models predicting root feeders would be negatively affected by competitively superior aboveground herbivores may be limited to early successional habitats or generalist root feeders attacking annual plants. In later successional habitats, root feeders become more abundant and appear to be the more potent force in driving plant performance and plant community composition. Aboveground herbivores, even at high population levels, were unable to prevent buildup of root herbivore populations and the resulting population collapse of their host plants. Significant information gaps exist about the impact of root feeders on plant physiology and secondary chemistry and their importance in natural areas, particularly in the tropics.
SELECTIVE TOXICITY OF NEONICOTINOIDS ATTRIBUTABLE TO SPECIFICITY OF INSECT AND MAMMALIAN NICOTINIC RECEPTORS
Authors: Tomizawa Motohiro , Casida John E.
Published: December 2002

▪ Abstract  Neonicotinoids, the most important new class of synthetic insecticides of the past three decades, are used to control sucking insects both on plants and on companion animals. Imidacloprid (the principal example), nitenpyram, acetamiprid, thiacloprid, thiamethoxam, and others act as agonists at the insect nicotinic acetylcholine receptor (nAChR). The botanical insecticide nicotine acts at the same target without the neonicotinoid level of effectiveness or safety. Fundamental differences between the nAChRs of insects and mammals confer remarkable selectivity for the neonicotinoids. Whereas ionized nicotine binds at an anionic subsite in the mammalian nAChR, the negatively tipped (“magic” nitro or cyano) neonicotinoids interact with a proposed unique subsite consisting of cationic amino acid residue(s) in the insect nAChR. Knowledge reviewed here of the functional architecture and molecular aspects of the insect and mammalian nAChRs and their neonicotinoid-binding site lays the foundation for continued development and use of this new class of safe and effective insecticides.
Novel, Magnetically Guided Catheter for Endocardial Mapping and Radiofrequency Catheter Ablation
Authors: Faddis Mitchell N. , Blume Walter , Finney Jennifer , Hall Andrew , Rauch John , Sell Jon , Bae Kyongtae Ty , Talcott Michael , Lindsay Bruce
Published: December 2002

Background—

Ablation of complex arrhythmias would be greatly facilitated by more precise control of ablation catheters. A feasibility study was performed in animals to evaluate a novel magnetic guidance system (MGS) that generates a magnetic field to control the movement and position of a magnetic ablation catheter.

Methods and Results—

The MGS is composed of a digital biplanar fluoroscope within an array of superconducting electromagnets that surround the torso of the experimental animal and a computer control system that generates a composite magnetic field for directional catheter deflection. Magnetic catheter navigation was performed in dogs and pigs (20 to 30 kg). A 7F magnetic ablation catheter was used for intracardiac navigation and radiofrequency ablation. The performance of a standard 7F deflectable catheter was not affected by the MGS. The magnetic catheter was navigated successfully to 51 predefined targets throughout the heart in 6 animals. In 5 animals, the magnetic catheter, guided by a 3D computed tomogram, was successfully navigated to all pulmonary veins. Navigation accuracy was estimated as <1 mm displacement from the target. The magnetic catheter was used to ablate the atrioventricular node in 4 animals and to perform linear ablations across the endocardial surface underlying an epicardial multielectrode recording plaque in 4 animals.

Conclusions—

These results demonstrate that the MGS can navigate and stabilize an ablation catheter at endocardial targets. Linear or focal radiofrequency ablation with the magnetic catheter is not compromised by the magnetic field. This technology provides precise control of endocardial catheters.
Clinical and Physiological Effects of an Acute α-1 Adrenergic Agonist and a β-1 Adrenergic Antagonist in Chronic Orthostatic Intolerance
Authors: Stewart Julian M. , Munoz Jose , Weldon Amy
Published: December 2002

Background—

Adrenergic agents are commonly used in the treatment of chronic orthostatic intolerance with postural tachycardia syndrome (POTS). POTS may be associated with increased limb blood flow (“high flow”) and defective orthostatic vasoconstriction or decreased limb blood flow (“low flow”) and potentially with small blood volume.

Methods and Results—

We investigated the consequences of short-term intravenous administration of an α-1 adrenergic agonist, phenylephrine, and a β-1 adrenergic antagonist, esmolol, in 14 patients with POTS aged 13 to 19 years. Indices of heart rate and blood pressure variability, peripheral blood flow, and arterial resistance were assessed, and the capacitance relation was computed for every subject using venous occlusion plethysmography. Patients were tilted to 35° upright while medicated and while unmedicated, and measurements were repeated. Phenylephrine improved orthostatic tolerance and normalized hemodynamics and indices of heart rate/blood pressure variability while supine and while upright, producing significant peripheral vasoconstriction and venoconstriction (20% capacitance change). Esmolol did not improve orthostatic tolerance or hemodynamics. A subgroup of low-flow POTS patients had exaggerated venoconstriction to phenylephrine (50% capacitance change) but others had no response.

Conclusions—

Phenylephrine, but not esmolol, improves orthostatic tolerance and hemodynamics in POTS. This lends support to the use of oral α-1 agonists in the treatment of patients with chronic orthostatic intolerance.
N-Terminal Pro-B–Type Natriuretic Peptide and Long-Term Mortality in Acute Coronary Syndromes
Authors: Omland Torbjørn , Persson Anita , Ng Leong , O’Brien Russel , Karlsson Thomas , Herlitz Johan , Hartford Marianne , Caidahl Kenneth
Published: December 2002

Background—

B-type natriuretic peptide (BNP) is a predictor of short- and medium-term prognosis across the spectrum of acute coronary syndromes (ACS). The N-terminal fragment of the BNP prohormone, N-BNP, may be an even stronger prognostic marker. We assessed the relation between subacute plasma N-BNP levels and long-term, all-cause mortality in a large, contemporary cohort of patients with ACS.

Methods and Results—

Blood samples for N-BNP determination were obtained in the subacute phase in 204 patients with ST-elevation myocardial infarction (MI): 220 with non-ST segment elevation MI and 185 with unstable angina in the subacute phase. After a median follow-up of 51 months, 86 patients (14%) had died. Median N-BNP levels were significantly lower in long-term survivors than in patients dying (442 versus 1306 pmol/L;
P
<0.0001). The unadjusted risk ratio of patients with supramedian N-BNP levels was 3.9 (95% confidence interval, 2.4 to 6.5). In a multivariate Cox regression model, N-BNP (risk ratio 2.1 [95% confidence interval, 1.1 to 3.9]) added prognostic information above and beyond Killip class, patient age, and left ventricular ejection fraction. Adjustment for peak troponin T levels did not markedly alter the relation between N-BNP and mortality. In patients with no evidence of clinical heart failure, N-BNP remained a significant predictor of mortality after adjustment for age and ejection fraction (risk ratio, 2.4 [95% confidence interval, 1.1 to 5.4]).

Conclusions—

N-BNP is a powerful indicator of long-term mortality in patients with ACS and provides prognostic information above and beyond conventional risk markers.
Visualization of Ventricular Thrombi With Contrast-Enhanced Magnetic Resonance Imaging in Patients With Ischemic Heart Disease
Authors: Mollet Nico R. , Dymarkowski Steven , Volders Wim , Wathiong Jurgen , Herbots Lieven , Rademakers Frank E. , Bogaert Jan
Published: December 2002

Background—

Ventricular thrombus formation is a frequent and potentially dangerous complication in patients with ischemic heart disease. Although transthoracic echocardiography (TTE) is generally used as diagnostic technique, we explored the role of contrast-enhanced (CE)-MRI to detect ventricular thrombi.

Methods and Results—

In 57 patients with acute myocardial infarction, chronic myocardial infarction, or ischemic cardiomyopathy, MRI was performed to evaluate ventricular function (CINE-MRI) and to depict presence of myocardial necrosis and/or scarring and no-reflow areas (CE-MRI). All studies were analyzed for concomitant ventricular thrombi. CE-MRI depicted 12 mural thrombi (3.1±2.9 cm
3
), located in left ventricular (LV) apex or adherent to anteroseptum, presenting as black, well-defined structures surrounded by bright contrast-enhanced blood. Thrombus formation on CE-MRI was related to larger end-diastolic volumes; lower ejection fractions; the region of delayed enhancement and lowest wall motion score, especially in left anterior descending coronary artery territory; and LV aneurysm formation. On CINE-MRI, thrombi were found in 6 patients. Nonvisualized thrombi were usually small (mean size 1.2±0.7 cm
3
). TTE depicted thrombi in 5. Nonvisualized lesions were most frequently located in LV apex and had a larger size than nonvisualized lesions on CINE-MRI (3.0±3.2 cm
3
). In 3 patients with suspected apical thrombus on TTE, MRI was normal.

Conclusions—

CE-MRI is not only an excellent technique to depict myocardial necrosis and scar tissue in patients with ischemic heart disease, but this study also suggests a better identification of LV thrombi than with presently used clinical imaging modalities, such as TTE.
Coffee Acutely Increases Sympathetic Nerve Activity and Blood Pressure Independently of Caffeine Content
Authors: Corti Roberto , Binggeli Christian , Sudano Isabella , Spieker Lukas , Hänseler Edgar , Ruschitzka Frank , Chaplin William F. , Lüscher Thomas F. , Noll Georg
Published: December 2002

Background—

Coffee is the most abundantly consumed stimulant worldwide. However, its cardiovascular safety remains controversial. Possible health hazards have been related to its main ingredient, caffeine. Activation of the sympathetic nervous system by coffee may enhance cardiovascular risk; however, it is unclear whether this effect of coffee is related to caffeine or other substance(s) also contained in decaffeinated coffee.

Methods and Results—

In 15 healthy volunteers (6 habitual and 9 nonhabitual coffee drinkers) arterial blood pressure (BP), heart rate, and muscle sympathetic nervous activity (MSA) were continuously recorded before and after drinking a triple espresso or a decaffeinated triple espresso or after intravenous administration of caffeine (250 mg) or placebo (saline) in the same subjects. There was a significant time × condition interaction for the intravenous caffeine and placebo conditions for MSA, with caffeine showing a significant increase in MSA at 60 minutes (53.2±14.1% total activity) and the placebo group showing no effect. A similar significant time effect was found for coffee drinking (54.1±22.5% total activity). Habitual and nonhabitual coffee drinkers demonstrated similar changes in MSA and BP after intravenous caffeine, whereas coffee drinking increased BP in nonhabitual drinkers only, despite comparable increases of MSA and plasma caffeine levels. Nonhabitual coffee drinkers showed similar activation of MSA and BP after caffeine infusion, coffee, or decaffeinated coffee.

Conclusions—

Acutely, coffee and caffeine induced comparable increases in MSA and BP in nonhabitual coffee drinkers, whereas habitual coffee drinkers exhibited lack of BP increase despite MSA activation to coffee. Because decaffeinated coffee also increases BP and MSA in nonhabitual drinkers, ingredients other than caffeine must be responsible for cardiovascular activation.
A Retrospective Review of the Use and Safety of Droperidol in a Large, High‐risk, Inner‐city Emergency Department Patient Population
Authors: Chase Peter B. , Biros Michelle H.
Published: December 2002

Droperidol (DROP) is used in the emergency department (ED) for sedation, analgesia, and its antiemetic effect. Its ED safety profile has not yet been reported in patients (pts). Objectives: To document the use of DROP in highrisk pts (those with head injury, alcohol or cocaine intoxication, and/or remote or recent seizures), and to determine the number of serious and minor adverse events (AEs)—seizures, hypotension, extrapyramidal side effects (EPSEs)—after DROP. Methods: The ED database (EmSTAT) was queried to determine who received intramuscular or intravenous DROP in the ED in 1998; further chart review was done if the patient was considered high risk for or had experienced an AE. Multiple regression analysis using a random‐effects model determined the significance of each variable in the occurrence of AEs. Results: 2,468 patients (aged 20 months to 98 years; 112 ≤17 years; 141 ≥66 years) received DROP for agitation (n = 1,357), pain (1,135), anxiety (99), vomiting (173), or other reasons (50). There were 945 pts considered high risk; 933 charts were reviewed (DROP mean dose 4.1 ± 2.0 mg); of these, 50 patient visits did not meet the criteria for high risk. There were 622 pts with head trauma (401 with alcohol use), including 47 with computed tomography (CT) scans positive for brain injury, 64 with cocaine use, and 197 with recent or remote seizures (137 with alcohol use). Minor AEs such as transient hypotension occurred in 96 pts after DROP (73 with alcohol use); 20 received intravenous fluids, while an additional 28 pts (8 with alcohol use) received rescue medications for EPSEs. Six possible serious AEs occurred in pts with serious comorbidities; 2 cases of respiratory depression, 3 post‐DROP seizures, and 1 cardiac arrest (resuscitated) 11 hours after DROP in a cocaine‐intoxicated pt (normal QT interval). There was no significant difference among high‐risk groups in the occurrence of AEs. Conclusions: The vast majority of pts who received DROP in the ED did not experience an AE. A few serious AEs were noted following DROP in patients with serious comorbidities; it is not clear that DROP was causative.
The price‐concentration relationship in grocery retailing: Retesting Newmark
Authors: Yu Chih‐ching , Connor John M.
Published: November 2002

A study by Newmark is one of two price‐concentration studies of U.S. grocery retailing that has failed to find a positive relationship. We examined four possible sources of experimental error in this study. The most important source of error was the failure to exclude noncompeting grocery retailers in the construction of the concentration measure. The relationship was also sensitive to controlling for a subgroup of observations from one state, to alternative data sources, and functional form. When these changes were made, concentration was found to be positively associated with the cost of groceries across cities. The relationship was significant despite a small nonrandom sample of cities and unscientifically sampled prices. [Econ Lit citations: L130, L810, L100] © 2002 Wiley Periodicals, Inc.
Marketing natural pork: An empirical analysis of consumers in the mountain region
Authors: Grannis Jennifer , Thilmany Dawn D.
Published: November 2002

The demand for organic meats, including beef and chicken, has grown dramatically in recent years. Yet, there are few branded pork products. This research examines the potential market for natural pork in the Intermountain West, with emphasis on targeting the market segment most likely to purchase this product at a significant premium. High‐income, frequent pork consumers, and those that have purchased natural beef are most likely to purchase natural pork products. With respect to production‐related attributes, those concerned about feed additives, and to a lesser degree, the effects of pork production on the environment, are likely target markets. [Econ‐Lit subject codes: M310, Q130] © 2002 Wiley Periodicals, Inc.
Explaining pricing conduct in a product‐differentiated oligopolistic market: An empirical application of a price conjectural variations model
Authors: Kinoshita Junko , Suzuki Nobuhiro , Kaiser Harry M.
Published: November 2002

A generalized Bertrand‐type model is applied to gain insights on Japanese firms' pricing conduct regarding milk beverages made from fresh milk and reconstituted milk. The empirical results, based on weekly scanner data, indicate the original Bertrand model is inappropriate for our empirical analysis. The estimated model resulted in substantially more elastic own‐price elasticities than previous estimates in Japan based on aggregate market data, supporting the Japanese retailers' contention that fluid milk is a more price‐elastic product than what previous studies had found. Incorporating estimated price conjectures into the model resulted in considerable discrepancies between partial and perceived own‐price elasticities. The result shows that a firm's price conjecture can be an important factor in determining the firm's perceived own‐price elasticity. The estimated conjectural variations were tested to determine whether they represent consistent pricing behavior, and the results indicated that consistent pricing behavior could not be statistically supported. [Econ‐Lit citations: Q110, Q130] © 2002 Wiley Periodicals, Inc.
Multicriteria analysis and assessment of financial viability of agribusinesses: The case of marketing co‐operatives and juice‐producing companies
Authors: Baourakis George , Doumpos Michael , Kalogeras Nikos , Zopounidis Constantin
Published: November 2002

Our main purpose here is to assess the viability of Greek companies that operate in the field of agricultural food‐production and marketing. More specifically, we present the basic operational framework within which the agricultural organizations of co‐operatives operate; we also examine the main features of the juice market. The analysis concerns the periods 1993–1998 (for the co‐operatives) and 1994–1998 (for juice‐producing firms), and is based upon the financial characteristics of 10 agricultural co‐operative organizations and 2 investor‐owned firms established and operating on the largest Greek island, Crete, and the 15 largest (in economic and financial terms) juice‐producing companies in Greece. The assessment procedure includes data analysis techniques in combination with a multicriteria analysis method (the PROMETHEE II method). The analysis results in an overall ranking of the examined firms' performance. This indicates the strengths and weaknesses of the firms involved with regard to their financial behavior, thereby contributing to the identification of the imperfections of the examined firms. © 2002 Wiley Periodicals, Inc.
Staggering and synchronisation of prices in a low‐inflation environment: Evidence from German food stores
Authors: Loy Jens‐Peter , Weiss Christoph
Published: November 2002

Only a few studies have analysed staggering and synchronisation in pricing behaviour of multiproduct firms. These studies used low‐frequency data in an environment of high rates of inflation. This article investigates staggering and synchronisation of weekly prices for 10 food products in 131 grocery stores in Germany over the period of May 1995 to December 2000 (296 weeks). Different forms of staggering and synchronisation (across‐store synchronisation, within type‐of‐store synchronisation, within‐retailer synchronisation, or across‐product synchronisation) have been analysed. None of these forms of synchronisation is supported empirically, however. In contrast, perfect staggering can only be rejected in very few cases, indicating that fixed or firm‐specific menu costs are not major causes for price stickiness. [JEL classification: L11, D40] © 2002 Wiley Periodicals, Inc.
The demand impacts of chicken contamination publicity—a case study
Authors: Dahlgran Roger A. , Fairchild Dean G.
Published: November 2002

Adverse publicity regarding food contamination can depress demand, causing lost producer revenue. This study addresses the magnitude of those losses through the analysis of the impact of TV and print news coverage of bacterial contamination of chicken in the United States. An inverse demand model for chicken is estimated using weekly data from 1982 through 1991. Our findings indicate adverse publicity about salmonella contamination of chicken depressed the demand for chicken, but that the effect was small, less than 1% during the period of maximum exposure. Further, consumers soon forget this news as they reverted to prior consumption patterns in a matter of weeks. [EconLit citation: D120] © 2002 Wiley Periodicals, Inc.
U.S. consumer preference and willingness‐to‐pay for domestic corn‐fed beef versus international grass‐fed beef measured through an experimental auction
Authors: Umberger Wendy J. , Feuz Dillon M. , Calkins Chris R. , Killinger‐Mann Karen
Published: November 2002

Experimental auction procedures were used to measure Chicago and San Francisco consumers' willingness‐to‐pay for beef flavor from domestic, corn‐fed beef versus Argentine, grass‐fed beef. Based on taste panel rankings and bid differentials between paired steak samples, consumers were grouped into one of three beef‐preference categories: corn‐fed beef preferring, grass‐fed beef preferring, and indifferent. A multinomial logit model and regression analysis were used to identify consumers who prefer a particular flavor of beef. On average, consumers were willing to pay a 30.6% premium for corn‐fed beef. Sixty‐two percent of the participants were willing to pay an average premium of $1.61 more per pound for the corn‐fed beef, 23% of the consumers were willing to pay a premium of $1.36 more per pound for the grass‐fed beef, only 15% of the consumers were indifferent. The results have important implications for country‐of‐origin labeling of beef products, as well as niche marketing of corn‐fed and grass‐fed beef. [EconLit citations: L110, L660, Q130]. © 2002 Wiley Periodicals, Inc.
The white shrimp futures market: Lessons in contract design and marketing
Authors: Sanders Dwight R. , Manfredo Mark R.
Published: November 2002

The successful introduction of futures contracts to industries unfamiliar with futures markets is likely to become increasingly important as futures exchanges move to alternative governance structures (e.g., for‐profit corporations), trading platforms evolve (i.e., electronic/Internet trading), and regulatory requirements relax. Here, we examine the performance of the Minneapolis Grain Exchange's white shrimp futures contract, one of the first futures contracts aimed at the aquaculture industry. Although the market structure largely conforms to the traditional criteria for a successful futures market, the contract's performance is disappointing in terms of liquidity, basis behavior, and ultimately, hedging effectiveness. Furthermore, nonpar‐size delivery options embedded in the contract design likely impact basis behavior for certain hedges. While these reasons contributed to the ultimate demise of the contract, a general lack of knowledge regarding futures markets among the shrimp industry was also a factor. Given these findings, pragmatic implications for the introduction and marketing of new futures contracts into new industries are discussed. [JEL/EconLit: Q130, Q140, G130] © 2002 Wiley Periodicals, Inc.
Minimum effective scale in export promotion
Authors: Richards Timothy J. , Patterson Paul M.
Published: November 2002

Nonprice promotion has long been used by small firms or organizations to increase agricultural exports. Some believe that export promotion in these cases is often unsuccessful as the promoter is unable to achieve the “critical mass” of awareness that is required for success. The objective of this article is to develop a theoretical explanation for the likely existence of minimum expenditure thresholds and to estimate their size using an econometric model of the optimal supply of advertising. An empirical example of apple promotion from Washington state (USA) finds minimum effective scale levels for four key promotion activities among several Latin American countries.[EconLit citations: C34, M37, Q17]. © 2002 Wiley Periodicals, Inc.
Assessment of CD24 expression on bone marrow neutrophilic granulocytes: CD24 Is a marker for the myelocytic stage of development
Authors: Elghetany M. Tarek , Patel Jyoti
Published: November 2002

The understanding of normal surface maturation pattern of granulocytes plays an essential role in identifying abnormal patterns, which may be of diagnostic or pathogenetic significance in some disorders, such as myclodysplastic syndromes. CD24, which is expressed only on granulocytes and not on monocytes, has not been adequately studied. Surface marker studies on eight control marrows indicate that CD24 is expressed on bone marrow granulocytes in a pattern that is similar to CD11b while much different than the more mature markers, CD16b and CD35. Three sorting experiments show that the majority of CD24− cells are promyelocytes. We conclude that CD24 is expressed on the neutrophilic granulocytes at the stage of myelocytes, and hence it could potentially be used to study normal and abnormal maturation of granulocytes. Am. J. Hematol. 71:348–349, 2002. © 2002 Wiley‐Liss, Inc.
Discontinuation of immunosuppression for prevention of kidney graft rejection after receiving a bone marrow transplant from the same HLA identical sibling donor
Authors: Gajewski James L. , Ippoliti Cindy , Ma Yan , Champlin Richard
Published: November 2002

Induction of tolerance in solid organ transplant recipients has been a long sought goal so that patients will not need lifelong immunosuppression. In this case report we review a patient who received a kidney transplant from an HLA matched related sibling and developed acute leukemia as a consequence of her immunosuppression. The patient was then treated with an allogeneic bone marrow transplant from her kidney donor. After the bone marrow transplant, all immunosuppression therapy for graft rejection and graft versus host disease was stopped. Six months after the bone marrow transplant, the patient's kidney function had no deterioration as a consequence of stopping immunosuppression. This illustrated that a combined solid organ/bone marrow transplant can help to induce tolerance. In fact, the tolerance to the bone marrow transplant for prevention of graft versus host disease may have been accomplished by the prior kidney transplant. Am. J. Hematol. 71:311–313, 2002. © 2002 Wiley‐Liss, Inc.
Randomized study comparing 4′‐epi‐doxorubicin (Epirubicin) versus doxorubicin as a part of induction treatment in adult acute lymphoblastic leukemia
Authors: Bhutani Manisha , Kumar Lalit , Vora Amish , Bhardwaj Narendra , Pathak Ashutosh Kumar , Singh Rajvir , Kochupillai Vinod
Published: November 2002

Doxorubicin or daunorubicin are routinely used to induce remission in acute lymphoblastic leukemia (ALL). Efficacy of epirubicin (an analog of doxorubicin), however, has not been adequately evaluated in ALL management. This randomized study was undertaken to compare the relative efficacy of epirubicin vs. doxorubicin as part of induction chemotherapy in adult ALL. Between January 1990 and June 1998, 79 previously untreated adult ALL patients (age 11–55 years, median 20 years) were randomized to receive either doxorubicin (Group A, n = 39) or epirubicin (Group B, n = 40) as a part of induction therapy. Vincristine and prednisolone were common in each group. The induction treatment was followed by identical consolidation and maintenance therapy. The two groups were compared as regards pretherapy clinical and laboratory parameters, dose intensity of therapy, therapeutic efficacy, myelotoxicity, and survival. Epirubicin was as effective as doxorubicin in terms of complete remission rate (80% vs. 78.3%; P = 0.87) and relapse rate (57.1% vs. 51.7%; P = 0.68). Five‐year overall survival (30% vs. 30%, P = 0.98) and disease‐free survival (40% vs. 39%, P = 0.92) at median follow‐up of 68 months was also similar in the two groups. The incidence of Grade 4 myelotoxicity was comparable in the two groups. Patients 20 years of age or less had better CR rates (90% vs. 65%; P = 0.011) and median overall survival (39 vs. 11 months; P = 0.008) compared to those who were older. From this study epirubicin appears as effective as doxorubicin as part of induction therapy for adult ALL. However, the results need to be validated on the basis of immunophenotype and cytogenetic prognostic characterization. Am. J. Hematol. 71:241–247, 2002. © 2002 Wiley‐Liss, Inc.