1,806 research outputs found
A Flexible Modeling Approach for Robust Multi-Lane Road Estimation
A robust estimation of road course and traffic lanes is an essential part of
environment perception for next generations of Advanced Driver Assistance
Systems and development of self-driving vehicles. In this paper, a flexible
method for modeling multiple lanes in a vehicle in real time is presented.
Information about traffic lanes, derived by cameras and other environmental
sensors, that is represented as features, serves as input for an iterative
expectation-maximization method to estimate a lane model. The generic and
modular concept of the approach allows to freely choose the mathematical
functions for the geometrical description of lanes. In addition to the current
measurement data, the previously estimated result as well as additional
constraints to reflect parallelism and continuity of traffic lanes, are
considered in the optimization process. As evaluation of the lane estimation
method, its performance is showcased using cubic splines for the geometric
representation of lanes in simulated scenarios and measurements recorded using
a development vehicle. In a comparison to ground truth data, robustness and
precision of the lanes estimated up to a distance of 120 m are demonstrated. As
a part of the environmental modeling, the presented method can be utilized for
longitudinal and lateral control of autonomous vehicles
Multi-Lane Perception Using Feature Fusion Based on GraphSLAM
An extensive, precise and robust recognition and modeling of the environment
is a key factor for next generations of Advanced Driver Assistance Systems and
development of autonomous vehicles. In this paper, a real-time approach for the
perception of multiple lanes on highways is proposed. Lane markings detected by
camera systems and observations of other traffic participants provide the input
data for the algorithm. The information is accumulated and fused using
GraphSLAM and the result constitutes the basis for a multilane clothoid model.
To allow incorporation of additional information sources, input data is
processed in a generic format. Evaluation of the method is performed by
comparing real data, collected with an experimental vehicle on highways, to a
ground truth map. The results show that ego and adjacent lanes are robustly
detected with high quality up to a distance of 120 m. In comparison to serial
lane detection, an increase in the detection range of the ego lane and a
continuous perception of neighboring lanes is achieved. The method can
potentially be utilized for the longitudinal and lateral control of
self-driving vehicles
Measurement of the CP violating phase phiS and the decay width difference DeltaGammaS in the decay B0s->J/psi phi with the ATLAS experiment
A feature of the neutral meson is that it can oscillate into its antiparticle before it decays, which can give rise to CP violation due to interference of the two processes mixing and decay. The time-dependent decay is characterized by the decay width and the decay width difference . The oscillation is governed by the mass difference , and the CP violation is described by the relative phase between the mixing and the decay. The analysis of the decay channel provides the possibility to test the predictions of the Standard Model of particle physics for those parameters. In particular the measurement of the CP violating phase has the capability to unveil enhancement of the small Standard Model value by New Physics. In this thesis the measurement of , and in the decay is presented. The analysis makes use of an integrated luminosity of that was collected with the ATLAS detector in collision produced by the LHC at a center-of-mass energy of . After the reconstruction and selection of the decay channel, a time-dependent angular analysis of the decay is performed. An untagged as well as a tagged analysis, using opposite side flavor tagging to determine the production flavor of the mesons, are presented. The parameters of interest are extracted through the application of an unbinned maximum likelihood fit method, which takes detector efficiency and resolution effects into account. A possible contribution from S-wave decays to the data sample as well as the contamination due to reflections from decays are incorporated in the fit. The result of the measurement is found to be consistent with the Standard Model prediction and is presented as , and confidence regions in the plane
Increased expression of autophagy protein LC3 in two patients with progressing chronic lymphocytic leukemia
Chronic lymphocytic leukemia (CLL) is the most common type of adult leukemia in the western hemisphere. It is characterized by a clonal proliferation of a population of CD5+ B lymphocytes that accumulate in the secondary lymphoid tissues, bone marrow, and blood. Some CLL patients remain free of symptoms for decades, whereas others rapidly become symptomatic or develop high-risk disease. Studying autophagy, which may modulate key protein expression and cell survival, may be important to the search for novel prognostic factors and molecules. Here, we applied flow cytometry technology to simultaneously detect autophagy protein LC3B with classical phenotypical markers used for the identification of tumoral CLL B cell clones. We found that two patients with progressing CLL showed increased expression of the autophagy protein LC3B, in addition to positive expression of CD38 and ZAP70 and unmutated status of IGHV. Our data suggest that activation of autophagy flux may correlate with CLL progression even before Ibrutinib treatment.Fil: Arroyo, Daniela Soledad. Universidad Nacional de CĂłrdoba. Facultad de Medicina; Argentina. Universidad Nacional de CĂłrdoba. Facultad de Ciencias QuĂmicas. Departamento de BioquĂmica ClĂnica; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: RodrĂguez, Cecilia InĂ©s. Universidad Nacional de CĂłrdoba. Facultad de Medicina; Argentina. Universidad Nacional de CĂłrdoba. Facultad de Ciencias QuĂmicas. Departamento de BioquĂmica ClĂnica; ArgentinaFil: Bussi, Claudio. The Francis Crick Institute; Reino Unido. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Manzone Rodriguez, Clarisa. Universidad Nacional de CĂłrdoba. Facultad de Ciencias QuĂmicas. Departamento de BioquĂmica ClĂnica; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico CĂłrdoba. Centro de Investigaciones en BioquĂmica ClĂnica e InmunologĂa; ArgentinaFil: Sastre, DarĂo. Universidad Nacional de CĂłrdoba. Facultad de Medicina; ArgentinaFil: Heller, Viviana. Universidad Nacional de CĂłrdoba. Facultad de Medicina; ArgentinaFil: Stanganelli, Carmen Graciela. Academia Nacional de Medicina de Buenos Aires. Instituto de Investigaciones HematolĂłgicas "Mariano R. Castex"; ArgentinaFil: Slavutsky, Irma Rosa. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Instituto de Medicina Experimental. Academia Nacional de Medicina de Buenos Aires. Instituto de Medicina Experimental; ArgentinaFil: Iribarren, Pablo. Universidad Nacional de CĂłrdoba. Facultad de Ciencias QuĂmicas. Departamento de BioquĂmica ClĂnica; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - CĂłrdoba; Argentin
First survey of centimeter-scale AC-LGAD strip sensors with a 120 GeV proton beam
We present the first beam test results with centimeter-scale AC-LGAD strip
sensors, using the Fermilab Test Beam Facility and sensors manufactured by the
Brookhaven National Laboratory. Sensors of this type are envisioned for
applications that require large-area precision 4D tracking coverage with
economical channel counts, including timing layers for the Electron Ion
Collider (EIC), and space-based particle experiments. A survey of sensor
designs is presented, with the aim of optimizing the electrode geometry for
spatial resolution and timing performance. Several design considerations are
discussed towards maintaining desirable signal characteristics with
increasingly larger electrodes. The resolutions obtained with several
prototypes are presented, reaching simultaneous 18 micron and 32 ps resolutions
from strips of 1 cm length and 500 micron pitch. With only slight
modifications, these sensors would be ideal candidates for a 4D timing layer at
the EIC
Characterization of BNL and HPK AC-LGAD sensors with a 120 GeV proton beam
We present measurements of AC-LGADs performed at the Fermilab's test beam
facility using 120 GeV protons. We studied the performance of various strip and
pad AC-LGAD sensors that were produced by BNL and HPK. The measurements are
performed with our upgraded test beam setup that utilizes a high precision
telescope tracker, and a simultaneous readout of up to 7 channels per sensor,
which allows detailed studies of signal sharing characteristics. These
measurements allow us to assess the differences in designs between different
manufacturers, and optimize them based on experimental performance. We then
study several reconstruction algorithms to optimize position and time
resolutions that utilize the signal sharing properties of each sensor. We
present a world's first demonstration of silicon sensors in a test beam that
simultaneously achieve better than 6-10 micron position and 30 ps time
resolution. This represents a substantial improvement to the spatial resolution
than would be obtained with binary readout of sensors with similar pitch
Age-associated modifications of intestinal permeability and innate immunity in human small intestine
The physical and immunological properties of the human intestinal epithelial barrier in aging are largely unknown. Ileal biopsies from young (7â12 years), adult (20â40 years) and aging (67â77 years) individuals not showing symptoms of gastrointestinal (GI) pathologies were used to assess levels of inflammatory cytokines, barrier integrity and cytokine production in response to microbial challenges. Increased expression of interleukin (IL)-6, but not interferon (IFN)Îł, tumour necrosis factor (TNF)-α and IL-1ÎČ was observed during aging; further analysis showed that cluster of differentiation (CD)11c+ dendritic cells (DCs) are one of the major sources of IL-6 in the aging gut and expressed higher levels of CD40. Up-regulated production of IL-6 was accompanied by increased expression of claudin-2 leading to reduced transepithelial electric resistance (TEER); TEER could be restored in in vitro and ex vivo cultures by neutralizing anti-IL-6 antibody. In contrast, expression of zonula occludens-1 (ZO-1), occludin and junctional-adhesion molecule-A1 did not vary with age and overall permeability to macromolecules was not affected. Finally, cytokine production in response to different microbial stimuli was assessed in a polarized in vitro organ culture (IVOC). IL-8 production in response to flagellin declined progressively with age although the expression and distribution of toll-like receptor (TLR)-5 on intestinal epithelial cells (IECs) remained unchanged. Also, flagellin-induced production of IL-6 was less pronounced in aging individuals. In contrast, TNF-α production in response to probiotics (VSL#3) did not decline with age; however, in our experimental model probiotics did not down-regulate the production of IL-6 and expression of claudin-2. These data suggested that aging affects properties of the intestinal barrier likely to impact on age-associated disturbances, both locally and systemically
The development of a knowledge test of depression and its treatment for patients suffering from non-psychotic depression: a psychometric assessment
<p>Abstract</p> <p>Background</p> <p>To develop and psychometrically assess a multiple choice question (MCQ) instrument to test knowledge of depression and its treatments in patients suffering from depression.</p> <p>Methods</p> <p>A total of 63 depressed patients and twelve psychiatric experts participated. Based on empirical evidence from an extensive review, theoretical knowledge and in consultations with experts, 27-item MCQ knowledge of depression and its treatment test was constructed. Data collected from the psychiatry experts were used to assess evidence of content validity for the instrument.</p> <p>Results</p> <p>Cronbach's alpha of the instrument was 0.68, and there was an overall 87.8% agreement (items are highly relevant) between experts about the relevance of the MCQs to test patient knowledge on depression and its treatments. There was an overall satisfactory patients' performance on the MCQs with 78.7% correct answers. Results of an item analysis indicated that most items had adequate difficulties and discriminations.</p> <p>Conclusion</p> <p>There was adequate reliability and evidence for content and convergent validity for the instrument. Future research should employ a lager and more heterogeneous sample from both psychiatrist and community samples, than did the present study. Meanwhile, the present study has resulted in psychometrically tested instruments for measuring knowledge of depression and its treatment of depressed patients.</p
Tinnitus in elderly patients and prognosis of mild-to-moderate congestive heart failure: a cross-sectional study with a long-term extension of the clinical follow-up
<p>Abstract</p> <p>Background</p> <p>The complex mechanism responsible for tinnitus, a symptom highly prevalent in elderly patients, could involve an impaired control of the microcirculation of the inner ear, particularly in patients with poor blood pressure control and impaired left ventricular (LV) function.</p> <p>Methods</p> <p>In order to define the relationship between the presence of tinnitus and the severity and clinical prognosis of mild-to-moderate chronic heart failure (CHF) in a large population of elderly patients (N = 958), a cross-sectional study was conducted with a long-term extension of the clinical follow-up. Blood pressure, echocardiographic parameters, brain natriuretic peptide (BNP), hospitalization, and mortality for CHF were measured. Multivariate logistic regression analysis was used to assess the association between the presence of tinnitus and some of the prognostic determinants of heart failure.</p> <p>Results</p> <p>The presence of tinnitus was ascertained in 233 patients (24.3%; mean age 74.9 ± 6 years) and was associated with reduced systolic and diastolic blood pressure (123.1 ± 16/67.8 ± 9 vs 125.9 ± 15/69.7 ± 9; <it>P </it>= .027/<it>P </it>= .006), reduced LV ejection fraction (LVEF%; 43.6 ± 15 vs 47.9 ± 14%, <it>P </it>= .001), and increased BNP plasma levels (413.1 ± 480 vs 286.2 ± 357, <it>P </it>= .013) in comparison to patients without symptoms. The distribution of CHF functional class was shifted toward a greater severity of the disease in patients with tinnitus. Combined one-year mortality and hospitalization for CHF (events/year) was 1.43 ± 0.2 in patients with tinnitus and 0.83 ± 0.1 in patients without tinnitus, with an adjusted hazard ratio (HR) of 0.61 (95% confidence interval (CI): 0.37 to 0.93, <it>P </it><.002).</p> <p>Conclusions</p> <p>Our preliminary data indirectly support the hypothesis that tinnitus is associated with a worse CHF control in elderly patients and can have some important clinical implications for the early identification of patients who deserve a more aggressive management of CHF.</p
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