Showing papers by "Ford Motor Company published in 1997"
TL;DR: While the main emphasis is on Linear-Quadratic optimal control and active suspensions, the paper also addresses a number of related subjects including semi-active suspensions; robust, adaptive and nonlinear control aspects and some of the important practical considerations.
779 citations
TL;DR: Posttraumatic stress disorder is more likely to develop in females than in males after exposure to a traumatic event, and susceptibility to PTSD in females might be greater in childhood than after age 15 years.
Abstract: Background: Epidemiologic surveys in the general population documented a higher rate of posttraumatic stress disorder (PTSD) in women than in men. To date, the finding has received little scientific attention. This study examines the extent to which sex differences in PTSD might be explained by previously identified risk factors and whether the sex difference in PTSD varied by age at exposure to traumatic events. Methods: The NIMH-DIS (NIMH Diagnostic Interview Schedule, Version III Revised) was used to measure DSM-IIIR disorders in a random sample of 1007 young adults. Cox proportional hazards models were used to estimate changes in the hazards ratio for PTSD associated with sex when potential risk factors were included. Results: Lifetime prevalence of exposure to traumatic events and number of traumatic events did not vary by sex. The prevalence of PTSD was higher for women than for men exposed to traumatic events (hazards ratio, 2.3; 95% confidence interval, 1.5-3.6). Preexisting anxiety disorders or major depressive disorders played a part in the observed sex difference in PTSD. Family history of anxiety disorder and early separation from parents, although significant risk factors for PTSD in subjects of both sexes, were unrelated to the sex difference in PTSD. The sex difference in PTSD was markedly greater if exposure occurred in childhood than later on. Conclusions: Posttraumatic stress disorder is more likely to develop in females than in males after exposure to a traumatic event. Susceptibility to PTSD in females might be greater in childhood than after age 15 years. Explanations of the sex difference might involve characteristics of individuals and of the traumatic experiences.
696 citations
TL;DR: Posttraumatic stress disorder influences the risk for first-onset major depression and alcohol use disorder and preexisting major depression increased women's vulnerability to the PTSD-inducing effects of traumatic events and risk for exposure to traumatic events.
Abstract: Background: The risk for first-onset major depression, anxiety, and substance use disorders associated with prior posttraumatic stress disorder (PTSD) was estimated in a sample of women. Methods: The National Institute of Mental Health Diagnostic Interview Schedule, revised according to DSMIII-R , was used to measure lifetime psychiatric disorders in a stratified random sample of 801 mothers of children, who participated in a study of cognitive and psychiatric outcomes by level of birth weight. Cox proportional hazards models with time-dependent covariates were used to calculate the hazards ratios of first onset of other disorders following PTSD. Results: The lifetime prevalence of traumatic events was 40% and of PTSD, 13.8%. Posttraumatic stress disorder signaled increased risks for first-onset major depression (hazards ratio, 2.1) and alcohol use disorder (hazards ratio, 3.0). The risk for major depression following PTSD was of the same magnitude as the risk for major depression following other anxiety disorders. Women with preexisting anxiety and PTSD had significantly increased risk for first-onset major depression. Additional analysis showed that preexisting major depression increased women's vulnerability to the PTSD-inducing effects of traumatic events and risk for exposure to traumatic events. Conclusions: Posttraumatic stress disorder influences the risk for first-onset major depression and alcohol use disorder. The causal explanation of these temporally secondary disorders is unclear and might involve the effect of PTSD or underlying vulnerabilities exposed by the traumatic experience.
545 citations
TL;DR: In this article, the authors report the successful application of a quantitative composite fingerprinting technique, incorporating both a rigorous statistical verification procedure for composite signatures and a multivariate mixing model, to evaluate sediment source type in the Dart catchment, Devon, UK and the Plynlimon experimental catchments, Powys, UK.
Abstract: We report the successful application of a quantitative composite fingerprinting technique, incorporating both a rigorous statistical verification procedure for composite signatures and a multivariate mixing model, to evaluate sediment source type in the Dart catchment, Devon, UK and the Plynlimon experimental catchment, Powys, UK. Quantitative ascription of source types is discussed in terms of the mean contributions and potential seasonal, inter- and intea-storm variations in the relative contributions of surface erosion from a number of distinct land use categories and of channel erosion to the suspended sediment load sampled at various sites within the study areas. Surface erosion of pasture soils is generally important in both study catchments but the impacts of spring and autumn cultivation in the Dart, and of autumn and winter forestry activity at Plynlimon, are also evident. Inter-storm variations in sediment source type reflect antecedent conditions, variable contributing areas and timing of sediment sample collection, and highlight the individuality of catchment response for the sampled flood events. Intra-storm variations in source type contributions emphasize the necessity for detailed sampling programmes for suspended sediment in storm periods, when using the fingerprinting approach to investigate sediment origin.
421 citations
TL;DR: Progress in this field is hampered by the inability to study cardiomyocytes from early, embryonal hearts because of their very small size and because of the lack of cardiac cell lines that mimic various stages of cardiac development.
Abstract: Time for primary review 20 days.
In order to study cardiac myocyte development different approaches were established during the last decades. The main purpose of these studies was the differentiation of cardiac precursor cells into specialized, differentiated cell types, as well as the development of functional properties such as Ca2+ handling, rhythm generation and excitation-contraction coupling of cardiomyocytes during development. Although considerable data exist about skeletal myogenesis [1–3], limited knowledge is available with regard to the origin of the commitment and differentiation of cardiac cells. A comprehensive, morphological study on the cytodifferentiation from mesenchymal cells into cardiac myocytes is described in the embryonic murine heart [4]: According to the authors, different stages of myofibrillogenesis are present during embryological myocardial development. Cells with no or only little myofibrillar arrangement develop to myocardial cells with orientated myofibrils [5, 6]. A number of morphological studies have investigated heart development on embryonic, neonatal and adult isolated cardiomyocytes also from different species [7–16].
Although the ultrastructure during cardiac development has been thoroughly investigated [17], still relatively little is known on the development of excitability of the mammalian heart, most importantly: (1): The relation between expression of cardio-specific genes (see review [23]), the formation of cardiac phenotypes and the functional expression of different types of ion channels; (2): The regulation and genetic control of expression of ion channels (e.g. by growth factors, hormones, extracellular matrix); (3): The development of the regulation of ion channels and morphological correlates. The progress in this field is hampered by the inability to study cardiomyocytes from early, embryonal hearts because of their very small size and because of the lack of cardiac cell lines that mimic various stages of cardiac development. The development of ion currents has been studied in cardiomyocytes prepared from mammalian embryos …
* Corresponding author. Tel.: (+49-221) 4786960; Fax: (+49-221) 4786965.
393 citations
05 Oct 1997
TL;DR: The analysis and design of current regulators for multi-phase AC loads is presented using complex vector notation and several ways of improving its performance are suggested and investigated.
Abstract: The analysis and design of current regulators for multiphase AC loads in AC machines is presented using complex vector notation. The use of complex vector notation provides a way of comparing the performance of controller topologies through their complex vector root locus and complex vector frequency-response functions. Limitations in the performance of the synchronous frame proportional plus integral current regulator are outlined and several ways of improving its performance are suggested and investigated.
335 citations
TL;DR: This model of embolic focal cerebral ischemia results in ischemic cell damage and provides a reproducible and predictable infarct volume which is relevant to thromboembolic stroke in humans and may be useful in documenting the safety and efficacy of fibrinolytic intervention and in investigating therapies complementary to antithrombotic therapy.
328 citations
TL;DR: The results indicate that children of depressed mothers have more internalizing problems, and depressed mothers overstate and overgeneralize their offspring's behavior problems.
Abstract: Objective To evaluate whether mothers' psychiatric history biases reports of their children's behavior problems, mothers' and teachers' reports of children's behavior problems were compared using a recently developed statistical approach. Method Child Behavior Checklists and Teacher's Report Forms were completed by mothers and teachers, respectively, about 801 six-year-old children. Mother's history of major depression, anxiety disorders, and substance use disorder was assessed by using the National Institute of Mental Health Diagnostic Interview Schedule. Generalized estimating equations were used for data analysis. Results According to both teachers and mothers, maternal history of major depression was associated with more internalizing problems; the association was significantly stronger when mothers were the informants. Mothers with history of any psychiatric disorder reported more externalizing problems in their children than expected, whereas teachers' reports of externalizing behaviors were unrelated to maternal psychiatric history. These findings could not be explained by variations in children's behaviors across settings. Conclusion The generalized estimating equation models enabled simultaneous examination of whether children of depressed mothers have excess behavior problems and whether depressed mothers overreport behavior problems in their children. The results indicate that children of depressed mothers have more internalizing problems. In addition, depressed mothers overstate and overgeneralize their offspring's behavior problems. This study broadens the concerns with reporting bias beyond maternal depression to include other psychiatric problems. The results emphasize the potential for bias in family history studies that rely on informants. J. Am. Acad. Child Adolesc. Psychiatry, 1997, 36(7):971–979.
256 citations
TL;DR: In this paper, XRD and TEM were used to measure the particle sizes of the various phases of the CeO 2 -Zr oxide solid solution and found that the particle size of the supported particulate phase decreased with increasing zirconium loading, but a discrepancy was noted between the XRD results and the TEM results.
241 citations
TL;DR: Many of the findings in the various syndromes of PE can be understood in terms of the severity of PE as it increases from mild with the pulmonary infarction syndrome to moderate with the isolated dyspnea syndrome to severe with circulatory collapse.
213 citations
Patent•
31 Dec 1997TL;DR: In this article, an engine control computer estimates the cumulative NOx storage in a NOx trap based on engine operating conditions and enters a purge mode of operation when a maximum storage capacity limit, based on trap temperature, is exceeded.
Abstract: An engine control computer estimates the cumulative NOx storage in a NOx trap based on engine operating conditions and enters a NOx purge mode of operation when a maximum storage capacity limit, based on trap temperature, is exceeded. The purge mode is terminated when NOx storage level decreases below a minimum storage capacity limit. The rate of NOx dissipation is also based on trap temperature.
Patent•
04 Aug 1997TL;DR: A wide variety of modifications may be made to the source object in order to form modified stereo images as discussed by the authors, and these modifications may involve modifying one or more images relative to the original image.
Abstract: Methods, devices and systems are provided which produce a synthesized stereoscopic image of a source image by forming at least two images from a source image where at least one image has been modified relative to the source image such that the images have a different spacial appearance than each other. A wide variety of modifications may be made to the source object in order to form modified stereo images. These modifications may involve modifying one or more images relative to the source image. For example, at least one image may be magnified, reduced, or rotated in the X, Y and/or Z plane relative to the source image. Alternatively or in addition, the position of one or more elements of one of the images may also be changed relative to the source image. Alternatively or in addition, at least one of the images may be transformed relative to the source image using a function which alters the position of elements of the image along the X or Y axis relative to the source image. In one variation, the function is a distorting algorithm, for example an elliptical or aspheric distorting algorithm which is not dependent on the depth information of the source image.
TL;DR: A fibrin-rich thrombotic focal cerebral ischemic model with reproducible and predictable infarct volume in rats is developed and may be useful in documenting the safety and efficacy of thrombolytic intervention as well as for investigating therapies complementary to antithrombosis therapy.
Abstract: We developed a fibrin-rich thrombotic focal cerebral ischemic model with reproducible and predictable infarct volume in rats. In male Wistar rats (n = 77), a thrombus was induced at the origin of t...
TL;DR: In this article, the chemical structures of P and S species in the X-ray absorption near edge structure (XANES) spectra of model compounds with known structure as fingerprints have been identified.
TL;DR: Daytime sleepiness was inversely related to hours of sleep and positively related to the ease of falling asleep at night; it varied significantly by employment and marital status.
Abstract: OBJECTIVES: Although excessive daytime sleepiness is associated with increased risks for accidents, decreased productivity, and interpersonal difficulties, information on its epidemiology is scarce. This paper examines correlates of and suspected risk factors for daytime sleepiness from a longitudinal epidemiological study of young adults. METHODS: The sample consisted of 1007 randomly selected young adults from a large health maintenance organization in southeast Michigan. Data were gathered in personal interviews conducted with 97% of the sample 5.5 years after baseline. Information on sleep characteristics in the last 2 weeks, including daytime sleepiness, nocturnal sleep onset, snoring, and hours of sleep, was collected on a self-administered instrument. Psychiatric disorders were measured by the National Institute of Mental Health's Diagnostic Interview Schedule. RESULTS: The average length of nocturnal sleep on weekdays was 6.7 hours. Daytime sleepiness was inversely related to hours of sleep and po...
TL;DR: It is shown that these systems, while not feedback linearizable, can be (globally) transformed by feedback and diffeomorphism into lower-triangular form and this transformation is employed to design a globally stabilizing controller with optimality properties and an input-to-state stability property with respect to matched uncertainties.
TL;DR: The 31‐kilodalton β‐galactoside‐binding protein galectin‐3 has been associated with cellular transformation and metastasis and its expression in human brain tumors and metastases to the central nervous system was examined.
Abstract: BACKGROUND
The 31-kilodalton β-galactoside-binding protein galectin-3 has been associated with cellular transformation and metastasis. Because neural tissues contain large amounts of glycoconjugates, and endogenous carbohydrate-binding proteins have been described in the human brain, the authors examined the expression of galectin-3 in human brain tumors and metastases to the central nervous system.
METHODS
Brain tumors were categorized by the World Health Organization system and galectin-3 expression by immunoperoxidase staining using a quantitative staining score.
RESULTS
Glioblastomas (Grade 4 astrocytomas) all stained strongly for galectin-3, whereas low grade astrocytomas (Grade 2) did not express the endogenous lectin. Anaplastic astrocytomas (Grade 3) exhibited intermediate expression. The staining score was significantly associated with tumor grade (P < 0.001). Normal brain tissue and benign tumors did not express galectin-3, whereas metastases to the brain were all positive for galectin-3 expression. Metastases expressed significantly more galectin-3 than the primary tumors from which they were derived (P = 0.003).
CONCLUSIONS
Galectin-3 expression correlates with the malignant potential of tumors in the central nervous system. Cancer 1997; 80:776-87. © 1997 American Cancer Society.
TL;DR: The selective expression of proteins associated with DNA damage, DNA repair and cell cycle observed in morphologically intact cells, ischemic injured cells and apoptotic cells suggests a differential role for these proteins in cell survival and apoptosis after stroke.
TL;DR: In this article, a steady state, CO-oxidation kinetics at 515 K have been measured on model, Pd catalysts, prepared by vapor deposition of Pd onto either zirconia, praseodymia, ceria, or a ceria-zirconica mixed oxide.
Abstract: Steady-state, CO-oxidation kinetics at 515 K have been measured on model, Pd catalysts, prepared by vapor deposition of Pd onto either zirconia, praseodymia, ceria, or a ceria-zirconia mixed oxide. A second rate process (RE2), associated with both the metal and the oxide support and observed previously on ceria-supported catalysts in excess CO [7], was also found for Pd supported on ceria-zirconia, but neither zirconia nor praseodymia had any effect on CO oxidation under the conditions of our study. For ceria and ceria-zirconia, deactivation, through the loss of RE2, caused by high-temperature calcination, was examined, with the Pd added after calcination so that the metal particle size was not a factor in deactivation. For ceria, there was a strong dependence on calcination temperature, with almost complete loss of RE2 above 1170 K. XRD showed that the loss was accompanied by a large increase in the crystallite size. Results for ceria-zirconia showed that the loss in this case was more gradual, with CO oxidation activity due to RE2 maintained to much higher calcination temperatures. Taking the importance of RE2 as a measure of the ability of the catalyst to use oxygen from the oxide, the implications of these results with respect to oxide structure and the effect of aging on oxygen-storage properties of reducible oxides are discussed.
TL;DR: There is a significant black/white, but not male/female difference in whole body bone mass and bone density before puberty, and ethnic and gender differences in bone and body composition suggest that the lean component may contribute to a greater peak bone mass in blacks vs. whites.
TL;DR: It is demonstrated that microglia exhibit a time dependent change in morphology after reperfusion and that the severity of injury may be reflected in the state of microglial activation.
Patent•
03 Sep 1997TL;DR: In this paper, a method for vehicle yaw rate estimation using two accelerometers and a steer angle sensor is presented, which combines two complimentary approaches to yaw-rate estimation using accelerometers.
Abstract: A method is provided for a vehicle yaw rate estimation using two accelerometers and a steer angle sensor. The new method combines two complimentary approaches to yaw rate estimation using accelerometers. A kinematic yaw rate estimate is weighted with a vehicle lateral acceleration at the center of gravity, and steering angle and vehicle forward speed are incorporated into a Kalman filter for estimating vehicle yaw rate based upon the kinematic yaw rate estimate, the lateral acceleration at the center of gravity, the vehicle steering angle, and the vehicle forward speed. The method incorporates use of either one or two accelerometers.
TL;DR: In this paper, the authors describe variations in water quality and chemical loads for UK rivers draining to the North Sea, which are related to regional differences in geology, climate, land use and population distribution.
Patent•
23 Dec 1997TL;DR: In this article, an isolated gate driver device for a power switching device having a plurality of transistors includes a primary circuit having a voltage source of a first voltage potential, and the secondary circuit also enables and disables each of the transistors based on the first and second load signals.
Abstract: An isolated gate driver device for a power switching device having a plurality of transistors includes a primary circuit having a voltage source of a first voltage potential. The primary circuit constantly switches the voltage source to generate first and second load signals based on control signals received from a microcontroller. The first load signal is modulated at a first frequency for enabling the transistors, and the second load signal is modulated at a second frequency, different from the first frequency, for disabling the transistors. A plurality of high frequency transformers corresponding to each of the transistors is coupled to the primary circuit. The transformers have a primary side for receiving one of the first and second load signals and a secondary side for transforming the one of the first and second load signals into corresponding signals at a second voltage potential. A secondary circuit coupled between each of the transformers and each of the corresponding transistors provides a bias power supply to each of the transistors at the second voltage potential. The secondary circuit also enables and disables each of the transistors based on the first and second load signals.
TL;DR: One hundred and three in-use vehicles, identified as high hydrocarbon and/or carbon monoxide emitters by remote sensing and roadside visual, underhood checks during a 1995 South Coast Air Quality Management District program, were tested on the IM240 cycle using a transportable dynamometer as mentioned in this paper.
Abstract: One hundred and three in-use vehicles, identified as high hydrocarbon and/or carbon monoxide emitters by remote sensing and roadside visual, underhood checks during a 1995 South Coast Air Quality Management District program, were tested on the IM240 cycle using a transportable dynamometer. Seventy-one of these vehicles were repaired as part of the program and were retested. Seventeen vehicles in the fleet initially emitted visible smoke from the tailpipe and were classified as "smokers". The fleet ranged in age from 6 to 22 years, with a median age of 12.3 years. Exhaust HC, CO, NOx, and particulate emissions (PM-10) were measured. PM-10 mass and the elemental and carbonaceous composition of the particulate matter were determined. The average fleet PM-10 emission rate was 0.138 g/mi, while the average emission rate for smokers was 0.395 g/mi. It was concluded that the casual observation of smoking vehicles was not very successful in identifying high PM-10 emitting vehicles. The particulate matter composition was primarily carbonaceous, with a variable distribution between the elemental and organic carbon fractions, and showed no significant difference in the percent organic carbon fraction between smokers and non-smokers. The PM composition differed, on average, between pre-repair and post-repair samples. The effect of the California Smog Check repair program on PM emission rates could not be evaluated due to concerns regarding the effect of vehicle conditioning on these measurements.
Patent•
27 Feb 1997TL;DR: In this paper, a hybrid electric vehicle (HEV) is equipped with an energy storage system (ESS) and the main power unit (HPU) and, using an optimal fuel cost strategy, scans all possible combinations of power from the HPU and ESS that satisfy the motive demand power.
Abstract: An operating strategy for a hybrid electric vehicle (HEV) manages the flow of energy to both supply the motive demand power of the HEV and maintain the charge of the energy storage system (ESS). A controller operates the main power unit (HPU) and ESS and, using an optimal fuel cost strategy, scans all possible combinations of power from the HPU and ESS that satisfy the motive demand power. The combination with the lowest fuel cost is selected and the ESS is charged, when possible, using marginal charging; but, if the state of charge of the ESS falls below a certain level, fast charging is invoked. A minimum power threshold strategy can be used rather than the fuel cost strategy. The minimum power threshold strategy determines the optimal compromise of HPU operation and ESS operation to maximize fuel economy by using a motive power threshold below which the HPU is not operated except to recharge the ESS.
TL;DR: The type of mucin that is normally limited to mucous glands is aberrantly expressed in surface mucous cells of H. pylori-positive patients, whereas less of the surface epithelium expresses normal surface-type gastric mucin.
TL;DR: The prevalence of PE limited to subsegmental pulmonary arteries is low, 6%, and was most prevalent among patients with low-probability ventilation/perfusion scans, particularly if they had no prior cardiopulmonary disease.
TL;DR: This pilot study suggests that investigation of earlier use of vasopressin as a therapeutic alternative in the treatment of cardiac arrest is warranted, and in this human model of prolonged cardiac arrest, 40% of the patients receiving vasopressingin had a significant increase in CPP.
Abstract: Objectives: To determine the hemodynamic effect of vasopressin on coronary perfusion pressure (CPP) in prolonged human cardiac arrest.
Methods: A prospective, open-label clinical trial of vasopressin during cardiac resuscitation was performed. Ten patients presenting in cardiac arrest initially received resuscitative measures by emergency physicians according to Advanced Cardiac Life Support (ACLS) gcidelines. A central venous catheter for fluid and drug administration and a femoral artery catheter for measurement of CPP (aortic minus right atrial relaxation phase pressures) were placed. When each patient was deemed nonsalvageable, 1.0 mg epinephrine was given and CPP was measured for 5 minutes, followed by a dose of vasopressin (1.O Ukg). CPP measurements were continued for another 5 minutes.
Results: The mean duration of cardiac arrest (out-of-hospital interval plus duration of ED ACLS) was 39.6 ± 16.5 min. There was no improvement in CPP after 1.0 mg of epinephrine. Vasopressin administration resulted in a significant increase of CPP in 4 of the 10 patients. Patients responding to vasopressin had a mean increase in CPP of 28.2 ± 16.4 mm Hg (range: 10–51.5), with these peak increases occurring at 15 seconds to 4 minutes after administration. The increases in the vasopressin levels after administration did not differ between the responders and nonresponders.
Conclusions: In this human model of prolonged cardiac arrest, 40% of the patients receiving vasopressin had a significant increase in CPP. This pilot study suggests that investigation of earlier use of vasopressin as a therapeutic alternative in the treatment of cardiac arrest is warranted.
TL;DR: In this article, absolute (flash photolysis) and relative (FTIR-smog chamber and GC) rate techniques were used to study the gas-phase reactions of Cl atoms with C2H6 (k1), C3H8 (k3), and n-C4H10 (k2) at 297 ± 1 K and 10−700 torr of N2 diluent, respectively.
Abstract: Absolute (flash photolysis) and relative (FTIR-smog chamber and GC) rate techniques were used to study the gas-phase reactions of Cl atoms with C2H6 (k1), C3H8 (k3), and n-C4H10 (k2) At 297 ± 1 K the results from the two relative rate techniques can be combined to give k2/k1 = (376 ± 020) and k3/k1 = (242 ± 010) Experiments performed at 298–540 K give k2/k1 = (20 ± 01)exp((183 ± 20)/T) At 296 K the reaction of Cl atoms with C3H8 produces yields of 43 ± 3% 1-propyl and 57 ± 3% 2-propyl radicals, while the reaction of Cl atoms with n-C4H10 produces 29 ± 2% 1-butyl and 71 ± 2% 2-butyl radicals At 298 K and 10–700 torr of N2 diluent, 1- and 2-butyl radicals were found to react with Cl2 with rate coefficients which are 31 ± 02 and 28 ± 01 times greater than the corresponding reactions with O2 A flash-photolysis technique was used to measure k1 = (575 ± 045) × 10−11 and k2 = (215 ± 015) × 10−10 cm3 molecule−1 s−1 at 298 K, giving a rate coefficient ratio k2/k1 = 374 ± 040, in excellent agreement with the relative rate studies The present results are used to put other, relative rate measurements of the reactions of chlorine atoms with alkanes on an absolute basis It is found that the rate of hydrogen abstraction from a methyl group is not influenced by neighboring groups The results are used to refine empirical approaches to predicting the reactivity of Cl atoms towards hydrocarbons Finally, relative rate methods were used to measure rate coefficients at 298 K for the reaction of Cl atoms with 1- and 2-chloropropane and 1- and 2-chlorobutane of (48 ± 03) × 10−11, (20 ± 01) × 10−10, (11 ± 02) × 10−10, and (70 ± 08) × 10−11 cm3 molecule−1 s−1, respectively © 1997 John Wiley & Sons, Inc Int J Chem Kinet 29: 43–55, 1997