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This paper investigates temporal correlations in human driving behavior using real-world driving to improve speed forecasting accuracy. These correlations can point to a measurement weighting function with two parameters: a forgetting factor for past speed measurements that the vehicle itself drove with, and a discount factor for the speeds of vehicles ahead based on information from vehicle-to-vehicle communication. The developed weighting approach is applied to a vehicle speed predictor using polynomial regression, a prediction method well-known in the literature. The performance of the developed approach is then assessed in both real-world and simulated traffic scenarios for accuracy and robustness. The new weighting method is applied to an ecological adaptive cruise control system, and its influence is analyzed on the prediction accuracy and the performance of the ecological adaptive cruise control in an electric vehicle powertrain model. The results show that the new prediction method improves energy saving from the eco-driving by up to 4.7% compared to a baseline least-square-based polynomial regression. This is a 10% improvement over the constant speed/acceleration model, a conventional speed predictor. [ABSTRACT FROM AUTHOR]

With the advent of self-driving autonomous vehicles, vehicle controllers are free to drive their own velocities. This feature can be exploited to drive an optimal velocity trajectory that minimizes fuel consumption. Two typical approaches to drive cycle optimization are velocity smoothing and tractive energy minimization. The former reduces accelerations and decelerations, and hence, it does not require information of vehicle parameters and resistance forces. On the other hand, the latter reduces tractive energy demand at the wheels of a vehicle. In this work, utilizing an experimentally validated full vehicle simulation software, we show that for conventional gasoline vehicles the lower energy velocity trajectory can consume as much fuel as the velocity smoothing case. This implies that the easily implementable, vehicle agnostic velocity smoothing optimization can be used for velocity optimization rather than the nonlinear tractive energy minimization, which results in a pulse-and-glide trajectory. [ABSTRACT FROM AUTHOR]

This paper presents a study of the energy-efficient operation of all-electric vehicles leveraging route information, such as road grade, to adjust the velocity trajectory. First, Pontryagin's maximum principle (PMP) is applied to derive necessary conditions and to determine the possible operating modes. The analysis shows that only five modes are required to achieve minimum energy consumption: full propulsion, cruising, coasting, full regeneration, and full regeneration with conventional braking. Then, the minimum energy consumption problem is reformulated and solved in the distance domain using dynamic programming to find the optimal speed profiles. Various simulation results are shown for a lightweight autonomous military vehicle. The sensitivity of energy consumption to regenerative-braking power limits and trip time is investigated. These studies provide important information that can be used in designing component size and scheduling operation to achieve the desired vehicle range. [ABSTRACT FROM AUTHOR]

Objectives: Effects of aging and leisure time physical activity (LPA) might influence the effect of occupational physical activity (OPA) on risk for cardiovascular disease (CVD). This study was conducted to determine whether OPA affects CVD after controlling the effects of LPA and other risk factors for CVD such as job stress. Methods: Participants were 131 male Korean manual workers. Tests for heart rate variability (HRV) were conducted for five minutes in the morning at work. We defined OPA as the combined concept of relative heart rate ratio (RHR), evaluated using a heart rate monitor. Results: Whereas high OPA was not related to any HRV items in the younger age group, high OPA was associated with an increased number of low-value cases among all HRV items in older workers. Exercise had beneficial effects only in the younger group. After controlling for exercise and other risk factors, the odds ratios of the root-mean square of the difference of successive normal R-R intervals (rMSSD) and high frequency band power (HF) among the older age and high OPA group compared with the younger age and low OPA group were 64.0 and 18.5, respectively. Social support and shift work were independent risk factors in HRV. Conclusions: OPA in aging workers increases CVD risks. This study provides support for the need for protection of aging workers from physical work overload, and indicates the need for further study of optimal limits of OPA. [ABSTRACT FROM AUTHOR]

Clinical studies suggest metabolic memory to hyperglycema. We tested whether diabetes leads to persistent systematic in vitro gene expression alterations in patients with type 1 diabetes (T1D) compared with their monozygotic, nondiabetic twins. Microarray gene expression was determined in skin fibroblasts (SFs) of five twin pairs cultured in high glucose (HG) for ~6 weeks. The Exploratory Visual Analysis System tested group differences in gene expression levels within KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways. An overabundance of differentially expressed genes was found in eight pathways: arachidonic acid metabolism (P = 0.003849), transforming growth factor-β signaling (P = 0.009167), glutathione metabolism (P = 0.01281), glycosylphosphatidylinositol anchor (P = 0.01949), adherens junction (P = 0.03134), dorsal-ventral axis formation (P = 0.03695), proteasome (P = 0.04327), and complement and coagulation cascade (P = 0.04666). Several genes involved in epigenetic mechanisms were also differentially expressed. All differentially expressed pathways and all the epigenetically relevant differentially expressed genes have previously been related to HG in vitro or to diabetes and its complications in animal and human studies. However, this is the first in vitro study demonstrating diabetes-relevant gene expression differences between TID-discordant identical twins. These SF gene expression differences, persistent despite the HG in vitro conditions, likely reflect "metabolic memory", and discordant identical twins thus represent an excellent model for studying diabetic epigenetic processes in humans. [ABSTRACT FROM AUTHOR]

This study was designed to elucidate the cellular basis of risk of or protection from nephropathy in patients with type 1 diabetes. Entry criteria included diabetes duration of 8 years (mean duration, 22.5 years) and glomerular filtration rate (GFR) >30 ml · min[sup −1] · 1.73 m[sup −2]. Patients were classified, on the basis of the estimated rate of mesangial expansion, as “fast-track” (upper quintile) or “slow-track” (lower quintile). A total of 88 patients were normoalbuminuric, 17 were microalbuminuric, and 19 were proteinuric. All three groups had increased glomerular basement membrane (GBM) width and mesangial fractional volume [Vv(Mes/glom)], with increasing severity from normoalbuminuria to microalbuminuria to proteinuria but with considerable overlap among groups. Vv(Mes/glom) (r = 0.75, P < 0.001) and GBM width (r = 0.63, P < 0.001) correlated with albumin excretion rate (AER), whereas surface density of peripheral GBM per glomerulus [Sv(PGBM/glom)] (r = 0.50, P < 0.001) and Vv(Mes/glom) (r = -0.48, P < 0.001) correlated with GFR. Vv(Mes/glom) and GBM width together explained 59% of AER variability. GFR was predicted by Sv(PGBM/glom), AER, and sex. Fast-track patients had worse glycemic control, higher AER, lower GFR, more hypertension and retinopathy, and, as expected, worse glomerular lesions than slow-track patients. Thus, there are strong relationships between glomerular structure and renal function across the spectrum of AER, but there is considerable structural overlap among AER categories. Given that normoalbuminuric patients may have advanced glomerulopathy, the selection of slow-track patients based on glomerular structure may better identify protected patients than AER alone. Diabetes 51:506–513, 2002 [ABSTRACT FROM AUTHOR]

The article discusses a study on microarray gene expression abnormalities in mitochondria related pathways in cultured skin fibroblasts of type 1 diabetic (T1D) patients. The study found significant differences between controls and T1D patients in several overlapping and related pathways relevant to mitochondrial function-electron transport-oxidative phosphorylation (OXPHOS)-oxidative stress, with no pathways expressed at lower levels in the diabetic group.

Recent advances in vehicle connectivity and automation technologies promote advanced control algorithms that co-optimize the longitudinal dynamics and powertrain operation of hybrid electric vehicles. Typically, a sequential optimization with the vehicle dynamics optimized followed by powertrain optimization is adopted to manage a number of complexities such as the inherent mixed-integer nature of the hybrid powertrain, the numerous state and control variables, the differing time scales of vehicle and powertrain subsystems, time-varying state constraints, and large horizon lengths. Instead, we solve the offline optimization problem in a centralize manner assuming exact knowledge of the lead vehicle's position over the entire trip by applying a discrete-time single shooting-based numerical approach, discrete mixed-integer shooting (DMIS), including a linearly increasing computational complexity to the problem horizon. In particular, the hierarchical problem structure is exploited to decompose the computationally intensive Hamiltonian minimization step into a set of low-dimensional optimizations. DMIS allows us to compute the direct fuel minimization problem including the vehicle and powertrain dynamics in a centralized manner to its full horizon while systematically tuning weighting factors that penalize passenger discomfort. For the first time, this study reveals that practically implemented sequential optimization exhibits similar fuel optimality as co-optimization when a certain level of passenger comfort is required. [ABSTRACT FROM AUTHOR]

Examines the presence of type VI collagen in glomeruli in type I diabetic patients using quantitative immunoelectron microscopy. Clinical characteristics of diabetes; Increase of glomerular basement membrane; Nature of extracellular matrix accumulation.

Pulmonary hemorrhage, a rare complication of Henoch-Schönlein purpura (HSP) reported primarily in adults and adolescents, is associated with significant mortality. Although it has been suggested that pulmonary hemorrhage also occurs in children with HSP, the few cases reported lack a clear differentiation from pauci-immune vasculitis. We report a prepubertal child with HSP, pulmonary hemorrhage, and immunofluorescence-documented IgA deposits on renal biopsy. Aggressive supportive management and steroid therapy led to successful recovery. A review of the current literature is presented. Because other conditions clinically mimic HSP, appropriate serological studies and a kidney biopsy to confirm the diagnosis should be performed in severely affected patients with renal disease. [ABSTRACT FROM AUTHOR]

Background: There are few published studies on the relationship between occupational lumbar load and facet joint degeneration (FJD). This cross-sectional study was conducted to evaluate the effect of physical lumbar load on FJD by comparing magnetic resonance imaging (MRI) findings of firefighters (FFs) and hospital office workers (HOWs). Methods: We randomly sampled 341 male FFs and 80 male HOWs by age stratification. A questionnaire and clinical examination, including MRI of the lumbar spine (T12-S1), were conducted. FJD was diagnosed and graded by using the classification of Pathria et al., and reclassified into two groups as follows: no FJD (grade 0) and FJD (grades 1, 2, and 3). The prevalence of FJD was analyzed according to occupational group. Results: The prevalence of FJD ranged from 31% (L1-L2) to 75% (L4-L5) in the FFs, and from 18% (L1-L2) to 69% (L4-L5) in the HOWs. After adjustment for age, body mass index, and frequency of physical exercise, the adjusted odds ratios (OR) for FJD in the FFs were significantly higher than those in the HOWs at all lumbar spinal levels, except for L3-L4 (L1-L2: OR, 2.644; 95% confidence interval [CI], 1.317-5.310; L2-L3: OR, 2.285; 95% CI, 1.304-4.006; L4-L5: OR, 1.918; 95% CI, 1.037-3. 544; L5-S1: OR, 1.811; 95% CI, 1.031-3.181). Conclusion: This study shows that FFs exhibit a greater likelihood of having FJD than HOWs after controlling for other risk factors of FJD. This suggests that the physical occupational demands of FFs affect their risk of developing FJD. [ABSTRACT FROM AUTHOR]

One of the main challenges of cosimulating hardware-in-the-loop (HIL) systems in real-time over the Internet is the fidelity of the simulation. The dynamics of the Internet may significantly distort the dynamics of the network-integrated system. This paper presents the development and experimental validation of an iterative learning control (ILC) based approach to improve fidelity of such networked system integration. Toward this end, a new metric for characterizing coupling fidelity is proposed, which, unlike some existing metrics, enables the formulation of the problem of improving system fidelity without requiring any knowledge about the reference dynamics (i.e., dynamics that would be observed, if the system was physically connected). Next, using this metric, the problem of improving fidelity is formulated as an ILC problem. The proposed approach is illustrated on an experimental setup simulating a hybrid electric powertrain distributed across three different sites with a real engine and battery in the loop. The conclusion is that the proposed approach holds significant potential for achieving high fidelity in Internet-distributed HIL (ID-HIL) simulation setups. [ABSTRACT FROM AUTHOR]

Nephropathic cystinosis is a lysosomal storage disorder, which, if untreated, results in renal failure by age 10 years. Oral cysteamine has been shown to preserve renal function in these patients. In this study, a 2-year-old girl with nephropathic cystinosis and severe gastrointestinal dysmotility was treated with intravenous (i.v.) administration of cysteamine hydrochloride (HCl). This is only the second report of long-term i.v. cysteamine therapy for nephropathic cystinosis. Unlike the treatment in the previous case, however, treatment in our patient was limited by liver toxicity. [ABSTRACT FROM AUTHOR]

Capsaicin, the va- nilloid that selectively activates vanilloid receptors (VRs) on sensory neurons for noxious perception, has been reported to increase cochlear blood flow (CBF). VR-related receptors have also been found in the inner ear. This study aims to address the question as to whether VRs exist in the organ of Corti and play a role in cochlear physiology. Capsaicin or the more potent VR agonist, resiniferatoxin (RTX), was infused into the scala tympani of guinea pig cochlea, and their effects on cochlear sensitivity were investigated. Capsaicin (20 µM) elevated the threshold of auditory nerve compound action potential and reduced the magnitude of cochlear microphonic and electrically evoked otoacoustic emissions. These effects were reversible and could be blocked by a competitive antagonist, capsazepine. Application of 2 µM RTX resulted in cochlear sensitivity alterations similar to that by capsaicin, which could also be blocked by capsazepine. A desensitization phenomenon was observed in the case of prolonged perfusion with either capsaicin or RTX. Brief increase of CBF by capsaicin was confirmed, and the endocochlear potential was not decreased. Basilar membrane velocity (BM) growth functions near the best frequency and BM tuning were altered by capsaicin. Immunohistochemistry study revealed the presence of vanilloid receptor type 1 of the transient receptor potential channel family in the hair cells and supporting cells of the organ of Corti and the spiral ganglion cells of the cochlea. The results indicate that the main action of capsaicin is on outer hair cells and suggest that VRs in the cochlea play a role in cochlear homeostasis. [ABSTRACT FROM AUTHOR]

Examines the role of tumor necrosis factor Alpha in the induction of mucous cell metaplasia in rat middle ear. Characterization of mucous cell hyperplasia; Factors stimulating mucous cell metaplasia; Presence of mucin-like glycoproteins in the middle ear effusion.

Pneumococcal otitis media is associated with the production of potent inflammatory mediators (leukotrienes), but the mechanism by which pneumococcus induces production of leukotrienes in the middle ear is poorly understood. In this study, up-regulation of 2 genes that govern the lipoxygenase pathway, cPLA2 and 5-LOX, was observed in rats following inoculation of pneumococcus into the middle ear cavity. Expression of cPLA2 was low, and 5-LOX gene expression was not detected in control animals. Up-regulation of cPLA2 and 5-LOX in middle ear epithelial cells was accompanied by an increase of high-molecular-weight glycoproteins in middle ear fluid and cells. These findings suggest that pneumococcus activates the lipoxygenase pathway by up-regulating expression of the cPLA2 and 5-LOX genes. This, in turn, may stimulate synthesis and secretion of high-molecular-weight glycoproteins that facilitate production of fluid in the middle ear cleft. [ABSTRACT FROM AUTHOR]

Evaluates the proximal tubular basement membrane width in insulin-dependent diabetes mellitus. Conduction of tubular basement membrane structure test; Measurement of orthogonal intercept method and mesangial and interstitial parameters; Determinants of the constellation of structural abnormalities in human diabetic nephropathy.