Showing papers by "Ford Motor Company published in 2001"

Therapeutic Benefit of Intravenous Administration of Bone Marrow Stromal Cells After Cerebral Ischemia in Rats

Abstract: Background and Purpose—We tested the hypothesis that intravenous infusion of bone marrow derived–marrow stromal cells (MSCs) enter the brain and reduce neurological functional deficits after stroke in rats. Methods—Rats (n=32) were subjected to 2 hours of middle cerebral artery occlusion (MCAO). Test groups consisted of MCAO alone (group 1, n=6); intravenous infusion of 1×106 MSCs at 24 hours after MCAO (group 2, n=6); or infusion of 3×106 MSCs (group 3, n=7). Rats in groups 1 to 3 were euthanized at 14 days after MCAO. Group 4 consisted of MCAO alone (n=6) and group 5, intravenous infusion of 3×106 MSCs at 7 days after MCAO (n=7). Rats in groups 4 and 5 were euthanized at 35 days after MCAO. For cellular identification, MSCs were prelabeled with bromodeoxyuridine. Behavioral tests (rotarod, adhesive-removal, and modified Neurological Severity Score [NSS]) were performed before and at 1, 7, 14, 21, 28, and 35 days after MCAO. Immunohistochemistry was used to identify MSCs or cells derived from MSCs in bra...

Intravenous Administration of Human Umbilical Cord Blood Reduces Behavioral Deficits After Stroke in Rats

Abstract: Background and Purpose— Human umbilical cord blood cells (HUCBC) are rich in stem and progenitor cells. In this study we tested whether intravenously infused HUCBC enter brain, survive, differentiate, and improve neurological functional recovery after stroke in rats. In addition, we tested whether ischemic brain tissue extract selectively induces chemotaxis of HUCBC in vitro. Methods— Adult male Wistar rats were subjected to transient (2-hour) middle cerebral artery occlusion (MCAO). Experimental groups were as follows: group 1, MCAO alone (n=5); group 2, 3×106 HUCBC injected into tail vein at 24 hours after MCAO (n=6) (animals of groups 1 and 2 were killed at 14 days after MCAO); group 3, MCAO alone (n=5); group 4, MCAO injected with PBS at 1 day after stroke (n=8); and group 5, 3×106 HUCBC injected into tail vein at 7 days after MCAO (n=5). Rats of groups 3, 4, and 5 were killed at 35 days after MCAO. Behavioral tests (rotarod and Modified Neurological Severity Score [mNSS]) were performed. Immunohistoc...

Modeling the formation of secondary organic aerosol within a comprehensive air quality model system

Abstract: The Secondary Organic Aerosol Model (SORGAM) has been developed for use in comprehensive air quality model systems. Coupled to a chemistry-transport model, SORGAM is capable of simulating secondary organic aerosol (SOA) formation including the production of low-volatility products and their subsequent gas/particle partitioning. The current model formulation assumes that all SOA compounds interact and form a quasi-ideal solution. This has significant impact on the gas/particle partitioning, since in this case the saturation concentrations of the SOA compounds depend on the composition of the SOA and the amount of absorbing material present. Box model simulations have been performed to investigate the sensitivity of the model against several parameters. Results clearly show the importance of the temperature dependence of saturation concentrations on the partitioning process. Furthermore, SORGAM has been coupled to the comprehensive European Air Pollution and Dispersion/Modal Aerosol Dynamics Model for Europe air quality model system, and results of a three-dimensional model application are presented. The model results indicate that assuming interacting SOA compounds, biogenic and anthropogenic contributions significantly influence each other and cannot be treated independently.

Periaqueductal gray matter dysfunction in migraine: cause or the burden of illness?

Abstract: Objective.—The periaqueductal gray matter (PAG) is at the center of a powerful descending antinociceptive neuronal network. We studied iron homeostasis in the PAG as an indicator of function in patients with episodic migraine (EM) between attacks and patients with chronic daily headache (CDH) during headache. High-resolution magnetic resonance techniques were used to map the transverse relaxation rates R2, R2*, and R2′ in the PAG, red nucleus (RN), and substantia nigra (SN). R2′ is a measure of non-heme iron in tissues. Methods.—Seventeen patients diagnosed with EM with and without aura, 17 patients diagnosed with CDH and medication overuse, and 17 normal adults (N) were imaged with a 3.0-tesla magnetic resonance imaging system. For each subject, mean values of the relaxation rates, R2 (1/T2), R2* (1/T2*), and R2′ (R2* − R2) were obtained for the PAG, RN, and SN. R2, R2*, and R2′ values of the EM, CDH, and N groups were compared using analysis of variance, Student t test, and correlation analysis. Results.—In the PAG, there was a significant increase in mean R2′ and R2* values in both the EM and CDH groups (P<.05) compared with the N group, but no significant difference in these values was demonstrated between the EM and CDH groups, or between those with migraine with or without aura in the EM group. Positive correlations were found for duration of illness with R2′ in the EM and CDH groups. A decrease in mean R2′ and R2* values also was observed in the RN and SN of the CDH group compared with the N and EM groups (P<.05), explained best by flow activation due to head pain. Conclusions.—Iron homeostasis in the PAG was selectively, persistently, and progressively impaired in the EM and CDH groups, possibly caused by repeated migraine attacks. These results support and emphasize the role of the PAG as a possible “generator” of migraine attacks, potentially by dysfunctional control of the trigeminovascular nociceptive system.

Treatment of traumatic brain injury in female rats with intravenous administration of bone marrow stromal cells.

Abstract: OBJECTIVE To study the effect of bone marrow stromal cells administered intravenously to female rats subjected to traumatic brain injury. METHODS We injected marrow stromal cells harvested from male rat bone marrow (n = 24) into the tail vein of the female rat (n = 8) 24 hours after traumatic brain injury; the rats were killed at Day 7 or 14 after treatment. The neurological function of the rats was evaluated using the rotarod test and the neurological severity score. The distribution of the male donor cells in brain, heart, lung, kidney, liver, muscle, spleen, and bone marrow of the female recipient rats was measured by identifying Y chromosome-positive cells using fluorescent in situ hybridization. RESULTS We found that marrow stromal cells injected intravenously significantly reduced motor and neurological deficits compared with control groups by Day 15 after traumatic brain injury (P < 0.05, analysis of covariance for repeated measures). The transplanted cells preferentially engrafted into the parenchyma of the injured brain and expressed the neuronal marker NeuN and the astrocytic marker glial fibrillary acidic protein. Marrow stromal cells were also found in other organs in female rats subjected to traumatic brain injury without any obvious adverse effects. CONCLUSION These data suggest that the intravenous administration of marrow stromal cells may be a promising therapeutic strategy that warrants further investigation for patients with traumatic brain injury.

Treatment of stroke in rat with intracarotid administration of marrow stromal cells

Abstract: Objective: To measure the therapeutic efficacy for the treatment of stroke with intra-arterial administration of bone marrow stromal cells (MSC). Background: MSC have characteristics of stem and progenitor cells. The hypothesis that MSC injected into the internal carotid artery after stroke enter into ischemic brain and improve neurologic recovery was tested. Methods: Twenty-five adult Wistar rats were subjected to transient (2-hour) middle cerebral artery occlusion alone (n = 9), or treated with intracarotid arterial injection of 200 μL phosphate-buffered saline (n = 8) or 2 × 106 MSC in 200 μL phosphate-buffered saline (n = 8) 1 day after ischemia. MSC were harvested and isolated from additional adult rats and then cultured and labeled with bromodeoxyuridine. Rats were subjected to neurologic functional tests (adhesive-removal, modified neurologic severity scores) before and at 1, 7, and 14 days after middle cerebral artery occlusion. Immunohistochemistry was used to identify cell-specific proteins of bromodeoxyuridine-reactive MSC. Results: Bromodeoxyuridine-reactive cells (∼21% of 2 × 106 injected MSC) distributed throughout the territory of the middle cerebral artery by 14 days after ischemia. Some bromodeoxyuridine-reactive cells expressed proteins characteristic of astrocytes and neurons. Rats with intra-arterial transplantation of MSC exhibited improvement on the adhesive-removal test (p Conclusions: MSC injected intra-arterially are localized and directed to the territory of the middle cerebral artery, and these cells foster functional improvement after cerebral ischemia.

Modeling the dynamic behavior of supercapacitors using impedance spectroscopy

Abstract: This paper presents a new approach of modeling the dynamic behavior of supercapacitors using impedance spectroscopy. The new Matlab/Simulink model can be used in simulating the voltage response and energy efficiency, e.g., for automotive power systems. The model in the frequency domain, the parameter calculation, as well as the inverse transformation into the time domain are discussed. Furthermore, simulation results are compared with experimental data. As application example, the new model is used to analyze the energy dissipation of a supercapacitor module installed in a 42-V mild-hybrid vehicle.

Control Lyapunov-Razumikhin functions and robust stabilization of time delay systems

Abstract: Motivated by control Lyapunov functions and Razumikhin theorems on stability of time delay systems, we introduce the concept of control Lyapunov-Razumikhin functions (CLRF). The main reason for considering CLRFs is construction of robust stabilizing control laws for time delay systems. Most existing universal formulas that apply to CLFs, are not applicable to CLRFs. It turns out that the domination redesign control law applies, achieving global practical stability and, under an additional assumption, global asymptotic stability. This additional assumption is satisfied in the practically important case when the quadratic part of a CLRF is itself a CLRF for the Jacobian linearization of the system. The CLRF based domination redesign possesses robustness to input unmodeled dynamics including an infinite gain margin. While, in general, construction of CLRFs is an open problem, we show that for several classes of time delay systems a CLRF can be constructed in a systematic way.

The epidemiology of posttraumatic stress disorder: what is the extent of the problem?

Abstract: Until recently, our understanding of posttraumatic stress disorder (PTSD) relied almost entirely on studies of war veterans and disaster victims. A handful of epidemiologic studies have now been conducted that investigate the natural course of PTSD as it occurs in the general population. Estimates of PTSD prevalence have tended to vary according to the diagnostic criteria used to define the disorder, assessment procedures, sample characteristics, and the definition of qualifying traumatic events. This article reviews key findings from these studies to provide insight into the burden of PTSD in the general population. Possible reasons for the observed difference in lifetime prevalence of PTSD between the sexes (a female-to-male lifetime prevalence ratio of 2:1 is typically reported) and factors thought to be associated with an increased risk for the disorder after exposure to trauma are reviewed.

Adult bone marrow stromal cells administered intravenously to rats after traumatic brain injury migrate into brain and improve neurological outcome.

Abstract: To measure effect of bone marrow stromal cells (MSCs) administered i.v. on rats subjected to traumatic brain injury (TBI), we injected MSCs labeled by BrdU into the tail vein 24 h after TBI and sacrificed rats 15 days later. The neurological severity score (NSS) and the Rotarod test were used to evaluate neurological function. The distribution of the donor cells in brain, heart, lung, kidney, liver and spleen were analyzed in recipient rats using immunohistochemical staining. MSCs injected i.v. significantly reduced motor and neurological deficits compared with control groups by day 15 after TBI. The cells preferentially entered and migrated into the parenchyma of the injured brain and expressed the neuronal marker NeuN and the astrocytic marker GFAP. MSCs were also found in other organs and primarily localized to the vascular structures, without any obvious adverse effects. Our data suggest that i.v. administration of MSCs may be useful in the treatment of TBI.

Src deficiency or blockade of Src activity in mice provides cerebral protection following stroke.

Abstract: Vascular endothelial growth factor (VEGF), an angiogenic factor produced in response to ischemic injury, promotes vascular permeability (VP). Evidence is provided that Src kinase regulates VEGF-mediated VP in the brain following stroke and that suppression of Src activity decreases VP thereby minimizing brain injury. Mice lacking pp60c-src are resistant to VEGF-induced VP and show decreased infarct volumes after stroke whereas mice deficient in pp59c-fyn, another Src family member, have normal VEGF-mediated VP and infarct size. Systemic application of a Src-inhibitor given up to six hours following stroke suppressed VP protecting wild-type mice from ischemia-induced brain damage without influencing VEGF expression. This was associated with reduced edema, improved cerebral perfusion and decreased infarct volume 24 hours after injury as measured by magnetic resonance imaging and histological analysis. Thus, Src represents a key intermediate and novel therapeutic target in the pathophysiology of cerebral ischemia where it appears to regulate neuronal damage by influencing VEGF-mediated VP.

Strategy to use an on-board navigation system for electric and hybrid electric vehicle energy management

Abstract: The present invention integrates an on-board navigation system to provide energy management for an electric vehicle (EV) and a hybrid electric vehicle (HEV). The HEV control strategy of the present invention accommodates the goals of fuel economy while always meeting driver demand for power and maintaining the functionality of the traction motor battery system using battery parameter controllers. In the preferred embodiment of the present strategy, a vehicle system controller tightly integrates the navigation system information with energy management while en route to a known destination. Present vehicle location is continuously monitored, expectations of driver demand are determined, and vehicle accommodations are made. The system can be configured to includes as part of its present vehicle location data on road patterns, geography with date and time, altitude changes, speed limits, driving patterns of a vehicle driver, and weather. The vehicle accommodations can be configured to use discrete control laws, fuzzy logic, or neural networks.

360° vision system for a vehicle

Abstract: A vehicle monitoring system including a camera mounted on top of the vehicle reflector in operative relation to the camera. The camera and the conical reflector provide a 360° field of view image around the vehicle. A controller is also included is adapted to detect objects within the field of view image, and determine a reference angle between the vehicle and a detected object. The controller also generates a distance value between the vehicle and the detected object as a function of a lane (w) and a reference angle (q). In one embodiment, the system includes an overhead-view display system including a reference vehicle indicator representative vehicle within the environment and an indicator element adapted to display the detected object with respect to the vehicle indicator as a function of the distance value.

A nitric oxide donor induces neurogenesis and reduces functional deficits after stroke in rats.

Abstract: The adult rodent brain is capable of generating neuronal progenitor cells in the subventricular zone, and in the dentate gyrus of the hippocampus, throughout the life of the animal. Signals that regulate progenitor cell proliferation, differentiation, and migration are not well known. We report that administration of a nitric oxide donor, (Z)-1-[N-(2-aminoethyl)-N-(2-ammonioethyl) aminio]diazen-1-ium-1,2-diolate (DETA/NONOate), to young adult rats significantly increases cell proliferation and migration in the subventricular zone and the dentate gyrus. Treatment with DETA/ NONOate also increases neurogenesis in the dentate gyrus. Furthermore, administration of DETA/NONOate to rats subjected to embolic middle cerebral artery occlusion significantly increases cell proliferation and migration in the subventricular zone and the dentate gyrus, and these rats exhibit significant improvements of neurological outcome during recovery from ischemic stroke. Administration of DETA/NONOate significantly increases cortical levels of guanosine monophosphate both in ischemic and nonischemic rats, supporting the role of nitric oxide in promoting cell proliferation and neurogenesis. Thus, our data indicate that nitric oxide is involved in the regulation of progenitor cells and neurogenesis in the adult brain. This suggests that nitric oxide delivered to the brain well after stroke may have therapeutic benefits.

Vehicle blind spot monitoring system

Abstract: A blind spot monitoring system for a vehicle includes two pairs of stereo cameras, two displays and a controller. The stereo cameras monitor vehicle blind spots and generate a corresponding pair of digital signals. The display shows a rearward vehicle view and may replace, or work in tandem with, a side view mirror. The controller is located in the vehicle and receives two pairs of digital signals. The controller includes control logic operative to analyze a stereopsis effect between each pair of stereo cameras and the optical flow over time to control the displays. The displays will show an expanded rearward view when a hazard is detected in the vehicle blind spot and show a normal rearward view when no hazard is detected in the vehicle blind spot.

Magnetorheological elastomers in tunable vibration absorbers

Abstract: Filling an elastomeric material with magnetizable particles leads to mechanical properties -shear moduli, tensile moduli, and magnetostriction coefficients - that are reversibly and rapidly controllable by an applied magnetic field. The origin of the field dependence of these properties is the existence of field-induced dipole magnetic forces between the particles. These 'smart' composites, which are sometimes termed magnetorheological (MR) elastomers, have been explored for use in a number of components, including automotive suspension bushings. In these and other applications, the tunability of the stiffness can enhance the compliance-control or vibration-transfer performance of the complex mechanical systems in which they are used. In the present study, we have constructed a simple one-degree-of-freedom mass-spring system - an adaptive tuned vibration absorber - that utilizes MR elastomers as variable-spring-rate elements. This device was used not only to explore the performance of such tunable components, but also to extend measurements of the shear moduli of these materials to higher frequencies than has previously been reported. We find that the field-induced increase in moduli of these materials is effective to mechanical frequencies well above 1 kHz, and that the moduli are consistent with the behavior expected for filled elastomers.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Eutectic nucleation and growth in hypoeutectic Al-Si alloys at different strontium levels

Abstract: The effects of different levels of strontium on nucleation and growth of the eutectic in a commercial hypoeutectic Al-Si foundry alloy have been investigated by optical microscopy and electron backscattering diffraction (EBSD) mapping by scanning electron microscopy (SEM). The microstructural evolution of each specimen during solidification was studied by a quenching technique at different temperatures and Sr contents. By comparing the orientation of the aluminum in the eutectic to that of the surrounding primary aluminum dendrites by EBSD, the eutectic formation mechanism could be determined. The results of these studies show that the eutectic nucleation mode, and subsequent growth mode, is strongly dependent on Sr level. Three distinctly different eutectic growth modes were found, in isolation or sometimes together, but different for each Sr content. At very low Sr contents, the eutectic nucleated and grew from the primary phase. Increasing the Sr level to between 70 and 110 ppm resulted in nucleation of independent eutectic grains with no relation to the primary dendrites. At a Sr level of 500 ppm, the eutectic again nucleated on and grew from the primary phase while a well-modified eutectic structure was still present. A slight dependency of eutectic growth radially from the mold wall opposite the thermal gradient was observed in all specimens in the early stages of eutectic solidification.

Intraarterial administration of marrow stromal cells in a rat model of traumatic brain injury.

Abstract: To test the efficacy of various delivery routes of stem cells to treat cerebral injury, we investigated the parenchymal distribution of marrow stromal cells (MSCs) injected into the internal carotid artery (ICA) of the adult rat after traumatic brain injury (TBI). Bromodeoxyuridine (BrdU)-labeled MSCs were injected via the ipsilateral ICA at 24 h after TBI. Using histology and immunohistochemistry, the distribution of implanted MSCs was analyzed at 7 days after transplantation. Four groups (n = 4/group) were studied: group 1, animals transplanted with MSCs cultured with NGF and BDNF at 24 h after TBI; group 2, animals transplanted with MSCs cultured without NGF and BDNF; group 3, animals injected with a placebo, phosphate buffered saline into the ICA at 24 h after TBI; and group 4, rats subjected to TBI only. In groups 1 and 2, BrdU-positive cells were localized to the boundary zone of the lesion, corpus callosum and cortex of the ipsilateral hemisphere. The number of BrdU-positive cells was significantly higher in the ipsilateral hemisphere than in the contralateral hemisphere. More MSCs infused intraarterially engrafted in group 1 (18.9%) than in group 2 (14.4%, p < 0.05). Using double staining, BrdU-positive cells expressed MAP-2, NeuN, and GFAP in both groups 1 and 2, with this expression being greater in group 1 and the difference between two groups reaching statistical significance in case of MAP-2. Our data suggest that intraarterial transplantation of MSCs is a viable route for the intracerebral administration of MSCs for the treatment of TBI, since MSCs infused intraarterially after TBI survive and migrate into the brain. Some implanted MSCs express proteins specific to neurons and astrocytes. The addition of NGF and BDNF promote migration of MSCs into the brain and subsequent expression of neuronal protein MAP-2.

Computer virus containment

Abstract: This invention provides a system for the prevention of the spread of a computer virus by intercepting outgoing messages from a computer device and determining whether the message is of an acceptable type. The system is provided as a firedoor that compares outgoing messages to a previously established list of approved actions and, if the message does not conform to an approved action on the list, the firedoor blocks transmission and prevents the virus from spreading any further. If a further embodiment, multiple firedoors are applied in a cascaded series to compare the transmission to different acceptance criteria in tandem.

Augmentation of tendon healing in an intraarticular bone tunnel with use of a bone growth factor

Abstract: We hypothesized that an exogenous bone growth factor could augment healing of a tendon graft in a bone tunnel in a rabbit anterior cruciate ligament-reconstruction model. Seventy rabbits underwent bilateral anterior cruciate ligament reconstructions with a semitendinosus tendon graft. One limb received a collagen sponge carrier vehicle containing a mixture of bone-derived proteins while the contralateral limb was treated with either no sponge or a sponge without bone-derived proteins. The reconstruction was evaluated at 2, 4, or 8 weeks with histologic, biomechanical, and magnetic resonance imaging analysis. Histologic analysis demonstrated that specimens treated with bone-derived proteins had a more consistent, dense interface tissue and closer apposition of new bone to the graft, with occasional formation of a fibrocartilaginous interface, when compared with control specimens. The treated specimens had significantly higher load-to-failure rates than did control specimens. Treatment with bone-derived proteins resulted in an average increase in tensile strength of 65%. The treated specimens were stronger than control specimens at each time point, but the difference was greatest at 8 weeks. On the basis of signal characteristics and new bone formation, magnetic resonance imaging was useful for predicting which limb was treated, the site of failure, and the limbs with higher load-to-failure values. This study demonstrates the potential for augmenting tendon healing in an intraarticular bone tunnel using an osteoinductive growth factor.

Metamodeling development for vehicle frontal impact simulation

Abstract: Response surface methods or metamodels are commonly used to approximate large computationally expensive engineering systems. Five response surface methods are studied: Stepwise Regression, Moving Least Square, Kriging, Multiquadric, and Adaptive and Interactive Modeling System. A real-world frontal impact design problem is used as an example, which is a complex, highly nonlinear, transient, dynamic, large deformation finite element model. To study the accuracy of the metamodel, the optimal Latin Hypercube Sampling method is used to distribute the sampling points uniformly over the entire design space. The Root Mean Square Error (RMSE) is used as the error indicator. Convergence rate, widely used in the arena of the finite element method for evaluating new element’s performance, was exploited in this vehicle impact example.

Evaluating the Performance of Building Thermal Mass Control Strategies

Abstract: A tool was developed that allows evaluation of thermal mass control strategies using HVAC utility costs as the baseline for comparison Inverse models are used to represent the behavior of the building, cooling plant, and air distribution system Inverse models use measured data to “learn” system behavior and provide relatively accurate site-specific performance predictions Based on weather and solar inputs, as well as occupancy and internal gains schedules and utility rates, the evaluation tool predicts the total HVAC utility cost for a specified control strategy Intelligent thermal mass control strategies can then be identified in a simulation environment using this analysis tool The evaluation tool was validated using data collected from a field site located near Chicago, Illinois The tool predicted HVAC utility costs for a summer month billing period that were within approximately 5% of actual costs Additional studies were performed to examine the utility savings potential for summertime operatio

Headlamp system with selectable beam pattern

Abstract: A headlamp system stores a plurality of beam patterns on a microprocessor 32 that selects a predetermined beam pattern based on driving conditions and sends the predetermined beam pattern to a digital micromirror device (DMD) 18 that is capable of generating the desired beam pattern by adjusting the position of individual pixels on the DMD 18. Several vehicle parameters are inputs 36, 37, 38, 29, 70 to the microcontroller 32 and are used to determine the appropriate beam pattern to be produced by the DMD 18 and projected by the headlamp system of the present invention.