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Various torque distribution and stability control algorithms have been studied along with the development of four-wheel drive vehicles. But, most of those algorithms focus only on performance improvement. Since the independent four-wheel drive system is based on four drive motors, faults can occur in a motor or an inverter. If a fault occurs, the vehicle stability is not guaranteed and a fatal accident can occur. In this study, the fault-tolerant stability control algorithm for remaining healthy motors is proposed. This fault-tolerant control (FTC) system contains torque distribution and stability control algorithms. For accurate control of motor allocation, driving conditions such as under/over-steering, and steering direction should be considered, as well as vehicle condition such as fault motor location and motor performance limits. The proposed FTC is evaluated with two fault conditions (e.g., front motor fault, rear motor fault) under straight acceleration and constant steering acceleration scenarios. The behavior characteristics and driving risks caused by failures of motors while driving are analyzed. Also, the FTC algorithm is accurately follow a desired path within a minimum error range that the driver can cover.

Despite development efforts toward autonomous vehicle technologies, the number of collisions and driver interventions of autonomous vehicles tested in California seems to be reaching a plateau. One of the main reasons for this is the lack of defensive driving functionality; i.e. emergency collision avoidance when other human drivers make mistakes. In this paper, a collision avoidance/mitigation system (CAMS) is proposed to rapidly evaluate risks associated with all surrounding vehicles and to maneuver the vehicle into a safer region when faced with critically dangerous situations. First, a risk assessment module, namely, predictive occupancy map (POM), is proposed to compute potential risks associated with surrounding vehicles based on relative position, velocity, and acceleration. Then, the safest trajectory with the lowest risk level is selected among the 12 local trajectories through the POM. To ensure stable and successful collision avoidance of the ego-vehicle, the lateral and longitudinal acceleration profiles are planned while considering the vehicle stability limit. The performance of the proposed algorithm is validated based on side and rear-end collision scenarios, which are difficult to predict and to monitor. The simulation results show that the proposed CAMS via POM detect a collision risk 1.4 s before the crash, and avoids the collision successfully.

In practice, many autonomous vehicle developers put a tremendous amount of time and efforts in tuning and calibrating the path tracking controllers in order to achieve robust tracking performance and smooth steering actions over a wide range of vehicle speed and road curvature changes. This design process becomes tiresome when the target vehicle changes frequently. In this study, a model-based Linear Quadratic Gaussian (LQG) Control with adaptive Q-matrix is proposed to efficiently and systematically design the path tracking controller for any given target vehicle while effectively handling the noise and error problems arise from the localization and path planning algorithms. The regulator, in turn, is automatically designed, without additional efforts for tuning at various speeds. The performance of the proposed algorithm is validated based on KAIST autonomous vehicle. The experimental results show that the proposed LQG with adaptive Q-matrix has tracking performance in both low (15kph) and high (45kph) speed driving conditions better than those of other conventional tracking methods like the Stanley and Pure-pursuit methods.

This study aimed to determine the factors influencing patients' choice of physician at the first visit through database analysis of a tertiary hospital in South Korea. We collected data on the first treatments performed by physicians who had treated patients for at least 3 consecutive years over 10 years (from 2003 to 2012) from the database of Seoul National University's affiliated tertiary hospital. Ultimately, we obtained data on 524,012 first treatments of 319,004 patients performed by 115 physicians. Variables including physicians' age and medical school and patients' age were evaluated as influencing factors for the number of first treatments performed by each physician in each year using a Poisson regression through generalized estimating equations with a log link. The number of first treatments decreased over the study period. Notably, the relative risk for first treatments was lower among older physicians than among younger physicians (relative risk 0.96; 95% confidence interval 0.95 to 0.98). Physicians graduating from Seoul National University (SNU) also had a higher risk for performing first treatments than did those not from SNU (relative risk 1.58; 95% confidence interval 1.18 to 2.10). Finally, relative risk was also higher among older patients than among younger patients (relative risk 1.03; 95% confidence interval 1.01 to 1.04). This study systematically demonstrated that physicians' age, whether the physician graduated from the highest-quality university, and patients' age all related to patients' choice of physician at the first visit in a tertiary university hospital. These findings might be due to Korean cultural factors.

Background and aims: Substantial research has examined the role of personality in disordered gambling. The predominant model in this work has been the five-factor model (FFM) of personality. In this study, we examined the personality correlates of gambling engagement and gambling severity using a six-dimensional framework known as the HEXACO model of personality, which incorporates FFM characteristics with the addition of honesty-humility. In addition, the potential mediating role of gambling motives in the personality and gambling severity relationship was explored. Methods: A sample of undergraduate gamblers (n = 183) and non-gamblers (n = 143) completed self-report measures of the Problem Gambling Severity Index (PGSI) and the Gambling Motives Questionnaire-Financial, as well as self- and observer report forms of the HEXACO-100. Results: Logistic regression results revealed that scores on honesty-humility were positively associated with non-gambling over gambling status. Furthermore, it was also found that honesty-humility, agreeableness, and conscientiousness were each uniquely associated with PGSI severity scores. The results of the mediational analyses suggest that each personality factor has different gambling motivational paths leading to PGSI gambling severity. Discussion and conclusions: The findings of this study contribute to the literature on behavioral addictions by providing an increased understanding of individual personality factors associated with likelihood of gambling, overall gambling severity, and gambling motives. Ultimately, these findings suggest that the honesty-humility dimension may be a target for the prevention efforts against problematic gambling outcomes. [ABSTRACT FROM AUTHOR]

Lactobacillus salivarius, a probiotic bacterium, encounters acidic conditions in its passage through the gastrointestinal tract of human and animal hosts. We studied the effect of a rapid downshift in extracellular pH from 6.5 to 4 on cell growth. The maximum growth rate was higher in low pH medium with glutathione supplementation than without. Cells developed a GSH-mediated acid-tolerance response and, when grown with 0.5 mM GSH, reached a higher final density than with other conditions. These findings suggest that the increased growth rate is caused by uptake of GSH which acts as a nutrient source as well as having protective functions, allowing for continued growth. [ABSTRACT FROM AUTHOR]

We report the acid tolerance response and changes in the level of protein expression of probiotic Lactobacillus reuteri subjected to transient (1.5 h) acid stress at pH 3.0. Sixteen acid-responsive proteins were identified by peptide mass fingerprinting including members of five broad functional categories: metabolism, transcription/translation, DNA replication/repair, transport and binding proteins, and pH homeostasis and stress responses. This work can provide some new and relevant information on the inducible mechanisms underlying the capacity of probiotic L. reuteri to tolerate acid stress. [ABSTRACT FROM AUTHOR]

This paper describes a simple new approach toward improving resolution of two-dimensional (2-D) protein gels used to explore the mammalian proteome. The method employs sample prefractionation using solution-phase isoelectric focusing (IEF) to split the mammalian proteome into well-resolved pools. As crude samples are thus prefractionated by p I range, very-narrow-pH-range 2-D gels can be subsequently employed for protein separation. Using custom pH partition membranes and commercially available immobilized pH gradient (IPG) strips, we maximized the total separation distance and throughput of seven samples obtained by prefractionation. Both protein loading capacity and separation quality were higher than the values obtained by separation of fractionated samples on narrow-pH-range 2-D gels; the total effective IEF separation distance was ~82 cm over the pH range pH 3–10. This improved method for analyzing prefractionated samples on narrow-pH-range 2-D gels allows high protein resolution without the use of large gels, resulting in decreased costs and run times. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

A problem in proteomic analysis of lung cancer tissue is the presence of complex components of different histological backgrounds (squamous cell carcinoma, small cell lung carcinoma, and adenocarcinoma). The efficient solubilization of protein components before two-dimensional electrophoresis (2-DE) is a very critical. Poor solubilization has been associated with a failure to detect proteins and diffuse, streaked and/or trailing protein spots. Here, we have optimized the solubilization of human lung cancer tissue to increase protein resolution. Isoelectric focusing (IEF) rehydration buffer containing a thiourea–urea mixture provided superior resolution, whereas a buffer without thiourea yielded consistently poor results. In addition, IEF rehydration buffers containing CHAPS and DTT gave superior resolution, whereas buffers containing Nonidet P-40 (NP-40) and/or Triton X-100 did not. A tributylphosphine-containing buffer gave consistently poor results. Using optimized conditions, we used 2-D gel analysis of human lung cancer tissue to identify 11 differentially-expressed protein spots by MALDI-mass spectrometry. This study provides a methodological tool to study the complex mammalian proteomes. [ABSTRACT FROM AUTHOR]

The article reports on a study on the evaluation of an effective sample prefractionation method for the proteome analysis of breast cancer tissue using narrow range two-dimensional gel electrophoresis. The study aims to optimize the solubilization of prefractionated human cancer cell samples using isoelectric focusing (IEF) rehydration buffers which contains a variety of reducing egents, detergents, chaotropes, and carrier ampholytes which are commercially available.

Abstract   Lactobacillus delbrueckii subsp. lactis strains were developed having increased activity, by gradually acclimatizing the bacteria to acidic conditions over repeated batch culture. Cells from one batch culture were used as the inoculum for the subsequent batch culture and thereby an adapted strain of Lactobacillus was obtained showing improved lactic acid productivity, cell growth and total glucose utilization. Furthermore, the acclimatized cells used significantly less nitrogen for a given level of lactic acid production, which is significant from an industrial point of view. The developed procedure decreases fermentation time and nutrient use, leading to reduced operation costs, while providing a lactic acid yield superior to previously reported methods. [ABSTRACT FROM AUTHOR]

Abstract  Lignin peroxidase has been extensively studied due to the potential use of this enzyme in environmental pollution control. Important aspects of the production of the enzyme by the white rot fungus,Phanerochaete chrysosporium, include the improvement of yield results and cell maintenance. In the present work,Phanerochaete chrysosporiumwas immobilized in polyurethane foam and used for repeated-batch fermentations with various dilution of the initial medium (D), and lignin peroxidase production was investigated. The peak of 283 ? 17.5 U lignin peroxidase/l production rate was obtained at aDof 1/5, with significantly lower production rates seen at higher and lower dilution ratios. When six cycles of repeated-batch fermentation were conducted using aDof 1/5, the results revealed that at least four cycles of repeated-batch fermentation were possible with a high lignin peroxidase production rate under a cut-off value of 178 ? 3.87 U/l. Furthermore, the cell-free culture broth could be successfully concentrated to 2,800 U/l by ultrafiltration. Thus, the present study shows that optimizing the dilution of the utilized nutritional medium can improve repeated batch production of lignin peroxidase from immobilizedP. chrysosporium, in terms of both cycle number and output. [ABSTRACT FROM AUTHOR]

During fed-batch cultivation of Escherichia coli K-12, the proteomic response to a temperature downshift from 37 to 20°C was quantitatively monitored and analyzed by using two-dimensional electrophoresis. When the temperature of exponentially growing E. coli K-12 culture was downshifted to 20°C, the synthesis level of 57 intracellular proteins showed significant changes for a prolonged period of time, compared to the fed-batch culture controlled at 37°C. Thus, these proteins are regarded as important stress proteins responsive to cold shock, which were analyzed by using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and identified using the E. coli SWISS-2DPAGE database. Most of the identified proteins were shown to be involved in energy metabolism, several cellular molecule biosynthetic pathways and catabolism, cell processes, flagellar biosynthesis and motility, and protein translation and folding. The systematic approach to the monitoring of proteomic responses and the detailed analysis results reported in this article would be useful in understanding the metabolic adaptation to lowered culture temperature and designing efficient fermentation strategies for the production of recombinant proteins and metabolites using E. coli strains. [ABSTRACT FROM AUTHOR]

The structure of personality variation is discussed from the perspective of the lexical approach, which is based on the examination of relations among personality-descriptive adjectives that are indigenous to various languages. The results of this approach—which reveal a cross-culturally replicated set of six dimensions—are described. Specifically, the obtained structure corresponds rather closely to the Five-Factor Model, but differs from that model in the nature of the Agreeableness and Emotionality/ Neuroticism factors and also in the existence of a sixth factor known as Honesty-Humility. It is suggested that the emergence of this structure provides support for attempts to establish a cross-culturally generalizable structural model that could summarize normal and abnormal personality variation. [ABSTRACT FROM AUTHOR]

We introduce a personality inventory designed to measure six major dimensions of personality derived from lexical studies of personality structure. The HEXACO Personality Inventory (HEXACO-PI) consists of 24 facet-level personality trait scales that define the six personality factors named Honesty-Humility (H), Emotionality (E). Extraversion (X), Agreeableness (A), Conscientiousness (C). and Openness to Experience (O). In this validation study involving a sample of over 400 respondents, all HEXACO-PI scales showed high internal consistency reliabilities, conformed to the hypothesized six-factor structure, and showed adequate convergent validities with external variables. The HEXACO factor space, and the rotations of factors within that space, are discussed with reference to J. S. Wiggins' work on the circumplex. [ABSTRACT FROM AUTHOR]