3,276 research outputs found
Modeliranje ljudske voĆŸnje primjenom po dijelovima linearnog modela
This paper presents development of the modeling strategy of the human driving behavior based on the expression as Piecewise Linear (PWL) model focusing on the driver\u27s stopping maneuver. The driving data are collected by using the three-dimensional driving simulator based on CAVE Automatic Virtual Environment (CAVE), which provides stereoscopic immersive virtual environment. In our modeling, the control scenario of the human driver, that is, the mapping from the driver\u27s sensory information to the operation of the driver such as acceleration, braking and steering, is expressed by Piecewise Linear (PWL) model. Since the PWL model includes both continuous behaviors given by polynomials and discrete logical conditions, it can be regarded as a class of Hybrid Dynamical System (HDS). The identification problem for the PWL model is formulated as the Mixed Integer Linear Programming (MILP) by transforming the switching conditions into binary variables. From the obtained results, it is found that the driver appropriately switches the \u27control law\u27 according to the sensory information. These results enable us to capture not only the physical meaning of the driving skill, but also the decision-making aspect (switching conditions) in the driver\u27s stopping maneuver.Ovaj Älanak prikazuje razvoj strategije modeliranja ljudskog ponaĆĄanja pri voĆŸnji, koja je utemeljena na po dijelovima linearnom (PWL) modelu fokusiranom na vozaÄev manevar zaustavljanja. Podaci o voĆŸnji prikupljeni su koriĆĄtenjem trodimenzionalnog simulatora voĆŸnje zasnovanog na CAVE Automatic Virtual Environment (CAVE) koji osigurava potpuno stereoskopsko virtualno okruĆŸenje. Pri modeliranju je upravljaÄki scenarij za vozaÄa, odnosno preslikavanje vozaÄevih senzorskih informacija u operacije poput ubrzanja, koÄenja i upravljanja vozilom, opisan PWL modelom. Kako PWL model ukljuÄuje istodobno kontinuirano ponaĆĄanje izraĆŸeno preko polinoma kao i diskretne logiÄke uvjete, takav se model moĆŸe promatrati kao klasa hibridnih dinamiÄkih sustava (HDS). Transformiranjem uvjeta prekapÄanja u binarne varijable, problem identifikacije PWL modela formuliran je kao mjeĆĄoviti cjelobrojni linearni program (MILP). Iz dobivenih je rezultata vidljivo da vozaÄ prekapÄa »zakon upravljanja« u skladu sa senzorskim informacijama. Rezultati omoguÄuju razumijevanje ne samo fizikalnog znaÄenja sposobnosti voĆŸnje veÄ i sam aspekt donoĆĄenja odluka (uvjeta prekapÄanja) prilikom vozaÄevog manevra zaustavljanja
Simultaneous deletion of floxed genes mediated by CaMKIIa-Cre in the brain and in male germ cells: application to conditional and conventional disruption of Go-alfa
The Cre/LoxP system is a well-established approach to spatially and temporally control genetic inactivation. The calcium/calmodulin-dependent protein kinase II alpha subunit (CaMKIIα) promoter limits expression to specific regions of the forebrain and thus has been utilized for the brain-specific inactivation of the genes. Here, we show that CaMKIIα-Cre can be utilized for simultaneous inactivation of genes in the adult brain and in male germ cells. Double transgenic Rosa26+/stop-lacZ::CaMKIIα-Cre+/Cre mice generated by crossing CaMKIIα-Cre+/Cre mice with floxed ROSA26 lacZ reporter (Rosa26+/stop-lacZ) mice exhibited lacZ expression in the brain and testis. When these mice were mated to wild-type females, about 27% of the offspring were whole body blue by X-gal staining without inheriting the Cre transgene. These results indicate that recombination can occur in the germ cells of male Rosa26+/stop-lacZ::CaMKIIα-Cre+/Cre mice. Similarly, when double transgenic Gnao+/f::CaMKIIα-Cre+/Cre mice carrying a floxed Go-alpha gene (Gnaof/f) were backcrossed to wild-type females, approximately 22% of the offspring carried the disrupted allele (GnaoÎ) without inheriting the Cre transgene. The GnaoÎ/Î mice closely resembled conventional Go-alpha knockout mice (Gnaoâ/â) with respect to impairment of their behavior. Thus, we conclude that CaMKIIα-Cre mice afford recombination for both tissue- and time-controlled inactivation of floxed target genes in the brain and for their permanent disruption. This work also emphasizes that extra caution should be exercised in utilizing CaMKIIα-Cre mice as breeding pairs.Fil: Choi, Chan-Il. Ajou University. School of Medicine; Corea del SurFil: Yoon, Sang-Phil. Ajou University. School of Medicine; Corea del SurFil: Choi, Jung-Mi. Ajou University. School of Medicine; Corea del SurFil: Kim, Sung-Soo. Ajou University. School of Medicine; Corea del SurFil: Lee, Young-Don. Ajou University. School of Medicine; Corea del SurFil: Birnbaumer, Lutz. National Institute of Environmental Health Sciences; Estados Unidos. Pontificia Universidad CatĂłlica Argentina "Santa MarĂa de los Buenos Aires". Instituto de Investigaciones BiomĂ©dicas. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Houssay. Instituto de Investigaciones BiomĂ©dicas; ArgentinaFil: Suh-Kim. Haeyoung. Ajou University. School of Medicine; Corea del Su
Striatal neuroinflammation promotes parkinsonism in rats
The specific role of neuroinflammation in the pathogenesis of Parkinson's disease remains to be fully elucidated. By infusing lipopolysaccharide (LPS) into the striatum, we investigated the effect of neuroinflammation on the dopamine nigrostriatal pathway. Here, we report that LPS-induced neuroinflammation in the striatum causes progressive degeneration of the dopamine nigrostriatal system, which is accompanied by motor impairments resembling parkinsonism. Our results indicate that neurodegeneration is associated with defects in the mitochondrial respiratory chain related to extensive S-nitrosylation/nitration of mitochondrial proteins. Mitochondrial injury was prevented by treatment of L-N^6^-(l-iminoethyl)-lysine, an inducible nitric oxide synthase (iNOS) inhibitor, suggesting that iNOS-derived NO is responsible for mitochondrial dysfunction. Furthermore, the nigral dopamine neurons exhibited intracytoplasmic [alpha]-synuclein and ubiquitin accumulation. These results demonstrate that degeneration of nigral dopamine neurons by neuroinflammation is associated with mitochondrial malfunction induced by NO-mediated S-nitrosylation/nitration of mitochondrial proteins
Modeliranje ljudske voĆŸnje primjenom po dijelovima linearnog modela
This paper presents development of the modeling strategy of the human driving behavior based on the expression as Piecewise Linear (PWL) model focusing on the driver\u27s stopping maneuver. The driving data are collected by using the three-dimensional driving simulator based on CAVE Automatic Virtual Environment (CAVE), which provides stereoscopic immersive virtual environment. In our modeling, the control scenario of the human driver, that is, the mapping from the driver\u27s sensory information to the operation of the driver such as acceleration, braking and steering, is expressed by Piecewise Linear (PWL) model. Since the PWL model includes both continuous behaviors given by polynomials and discrete logical conditions, it can be regarded as a class of Hybrid Dynamical System (HDS). The identification problem for the PWL model is formulated as the Mixed Integer Linear Programming (MILP) by transforming the switching conditions into binary variables. From the obtained results, it is found that the driver appropriately switches the \u27control law\u27 according to the sensory information. These results enable us to capture not only the physical meaning of the driving skill, but also the decision-making aspect (switching conditions) in the driver\u27s stopping maneuver.Ovaj Älanak prikazuje razvoj strategije modeliranja ljudskog ponaĆĄanja pri voĆŸnji, koja je utemeljena na po dijelovima linearnom (PWL) modelu fokusiranom na vozaÄev manevar zaustavljanja. Podaci o voĆŸnji prikupljeni su koriĆĄtenjem trodimenzionalnog simulatora voĆŸnje zasnovanog na CAVE Automatic Virtual Environment (CAVE) koji osigurava potpuno stereoskopsko virtualno okruĆŸenje. Pri modeliranju je upravljaÄki scenarij za vozaÄa, odnosno preslikavanje vozaÄevih senzorskih informacija u operacije poput ubrzanja, koÄenja i upravljanja vozilom, opisan PWL modelom. Kako PWL model ukljuÄuje istodobno kontinuirano ponaĆĄanje izraĆŸeno preko polinoma kao i diskretne logiÄke uvjete, takav se model moĆŸe promatrati kao klasa hibridnih dinamiÄkih sustava (HDS). Transformiranjem uvjeta prekapÄanja u binarne varijable, problem identifikacije PWL modela formuliran je kao mjeĆĄoviti cjelobrojni linearni program (MILP). Iz dobivenih je rezultata vidljivo da vozaÄ prekapÄa »zakon upravljanja« u skladu sa senzorskim informacijama. Rezultati omoguÄuju razumijevanje ne samo fizikalnog znaÄenja sposobnosti voĆŸnje veÄ i sam aspekt donoĆĄenja odluka (uvjeta prekapÄanja) prilikom vozaÄevog manevra zaustavljanja
Scoring Method for Early Prediction of Neonatal Chronic Lung Disease Using Modified Respiratory Parameters
In our previous study, we have demonstrated that peak inspiratory pressure over birth weight (PIP/kg) and mean airway pressure over birth weight (MAP/kg) were more significant risk factors for the development of neonatal chronic lung disease (CLD) than PIP and MAP. We aimed to develop a scoring method using the modified respiratory variables (SMUMRV) to predict CLD at early postnatal period. From 1997 to 1999, a retrospective review was performed for 197 infants <1,500 g for the development of the SMUMRV based on statistical analysis. From 2000 to 2001, calculated scores on day 4, 7 and 10 of life were obtained prospectively for 107 infants <1,500 g. Predictive values and the area under the receiver operator characteristic curve (AUC) were determined and compared with the result of the previous regression model. Gestational age, birth weight, 5 min Apgar score, PIP/kg at 12 hr of age, fractional inspired oxygen (FiO2), MAP/kg, modified oxygenation index and ventilatory mode were selected as parameters of SMUMRV. No significant differences of AUCs were found between the SMUMRV and the Yoder model. It is likely that our scoring method provides reliable values for predicting the development of CLD in very low birth weight infants
Molecular mechanisms of heptaplatin effective against cisplatin-resistant cancer cell lines: less involvement of metallothionein
BACKGROUND: Heptaplatin is a new platinum derivative with anticancer activity against various cancer cell lines, including cisplatin-resistant cancer cell lines (Cancer Chemother Pharmacol 1995; 35: 441). METHODS: Molecular mechanisms of heptaplatin effective against cisplatin-resistant cancer cell lines has been investigated in connection with metallothionein (MT). Cytotoxicity was determined by an MTT assay. MT mRNA, was determined by RT-PCR assay. Transfection study was carried out to examine the function of MT. RESULTS: Of various gastric cancer cell lines, SNU-638 and SNU-601 showed the highest and lowest levels of MT mRNA, respectively, showing 80-fold difference. The IC(50 )values of SNU-638 to cisplatin, carboplatin and heptaplatin were 11.2-fold, 5.1-fold and 2.0-fold greater than those of SNU-601, respectively. Heptaplatin was more effective against cisplatin-resistant and MT-transfected gastric cancer sublines than cisplatin or carboplatin was. In addition, heptaplatin attenuated cadmium, but not zinc, induction of MT. CONCLUSION: These results indicate that molecular mechanisms of heptaplatin effective against cisplatin-resistant gastric cancer sublines is at least in part due to the less involvement of MT in heptaplatin resistance as well as its attenuation of MT induction
Primary T-cell Lymphoma of the Thyroid Associated with Hashimoto's Thyroiditis, Histologically Mimicking MALT-Lymphoma
Most of thyroid lymphomas are B-lineage, and T-cell lymphomas are rare. Here, we report a case of primary thyroid T-cell lymphoma associated with Hashimoto's thyroiditis. A 48-yr-old woman presented with incidentally found neck mass. Histologically, the resected right lobe of the thyroid was replaced by monomorphic small atypical lymphoid cells with lymphoepithelial lesion-like change, most of which were immunoreactive for CD3, CD8, ÎČF-1, and TIA-1. Peripheral T-cell lymphoma, unspecified, was finally diagnosed after molecular study for TCR-Îł gene rearrangement. This is the second case of cytotoxic T-cell lymphoma reported in the thyroid gland so far. Unique association between thyroid follicles and neoplastic lymphocytes may be characteristic feature of this type of T-cell lymphoma
Primary Cardiac Angiosarcoma Presenting With Cardiac Tamponade
Primary cardiac angiosarcoma is a very rare disease with a poor prognosis. We report a case of a patient with a primary cardiac angiosarcoma who presented with cardiac tamponade; the angiosarcoma was successfully resected surgically
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