133 research outputs found

    Properties of the ground 3^3F2_2 state and the excited 3^3P0_0 state of atomic thorium in cold collisions with 3^3He

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    We measure inelastic collisional cross sections for the ground 3^3F2_2 state and the excited 3^3P0_0 state of atomic thorium in cold collisions with 3^3He. We determine for Th (3^3F2_2) at 800 mK the ratio γ500\gamma \approx 500 of the momentum-transfer to Zeeman relaxation cross sections for collisions with 3^3He. For Th (3^3P0_0), we study electronic inelastic processes and find no quenching even after 10610^6 collisions. We also determine the radiative lifetime of Th (3^3P0_0) to be τ>130\tau > 130 ms. This great stability of the metastable state opens up the possibility for further study, including trapping

    Vibrational quenching of the electronic ground state in ThO in cold collisions with 3^3He

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    We measure the ratio γ\gamma of the momentum-transfer to the vibrational quenching cross section for the X (1Σ+^1\Sigma^+), ν=1\nu=1, J=0\mathrm{J=0} state of molecular thorium monoxide (ThO) in collisions with atomic 3^3He between 800 mK and 2.4 K. We observe indirect evidence for ThO--He van der Waals' complex formation, which has been predicted by theory. We determine the 3-body recombination rate constant Γ3\Gamma_3 at 2.4 K, and establish that the binding energy Eb>_b > 4 K

    Quantitative image analysis of intra-tumoral bFGF level as a molecular marker of paclitaxel resistance

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    <p>Abstract</p> <p>Background</p> <p>The role of basic fibroblast growth factor (bFGF) in chemoresistance is controversial; some studies showed a relationship between higher bFGF level and chemoresistance while other studies showed the opposite finding. The goal of the present study was to quantify bFGF levels in archived tumor tissues, and to determine its relationship with chemosensitivity.</p> <p>Methods</p> <p>We established an image analysis-based method to quantify and convert the immunostaining intensity of intra-tumor bFGF to concentrations; this was accomplished by generating standard curves using human xenograft tumors as the renewable tissue source for simultaneous image analysis and ELISA. The relationships between bFGF concentrations and tumor chemosensitivity of patient tumors (n = 87) to paclitaxel were evaluated using linear regression analysis.</p> <p>Results</p> <p>The image analysis results were compared to our previous results obtained using a conventional, semi-quantitative visual scoring method. While both analyses indicated an inverse relationship between bFGF level and tumor sensitivity to paclitaxel, the image analysis method, by providing bFGF levels in individual tumors and therefore more data points (87 numerical values as opposed to four groups of staining intensities), further enabled the quantitative analysis of the relationship in subgroups of tumors with different pathobiological properties. The results show significant correlation between bFGF level and tumor sensitivity to the antiproliferation effect, but not the apoptotic effect, of paclitaxel. We further found stronger correlations of bFGF level and paclitaxel sensitivity in four tumor subgroups (high stage, positive p53 staining, negative aFGF staining, containing higher-than-median bFGF level), compared to all other groups. These findings suggest that the relationship between intra-tumoral bFGF level and paclitaxel sensitivity was context-dependent, which may explain the previous contradictory findings on the merit of using plasma or urine bFGF level as a prognostic indicator.</p> <p>Conclusion</p> <p>The present study established a quantitative image analysis method that enabled the measurement of intratumoral bFGF level in archived tissues. The ability to quantify a potential biomarker provided the opportunity to study the relationship between the biomarker and chemosensitivity in tumor subgroups and thereby enabled hypothesis generation for additional translational research.</p

    Large spin relaxation rates in trapped submerged-shell atoms

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    Spin relaxation due to atom-atom collisions is measured for magnetically trapped erbium and thulium atoms at a temperature near 500 mK. The rate constants for Er-Er and Tm-Tm collisions are 3.0 times 10^-10 cm^3 s^-1 and 1.1 times 10^-10 cm^3 s^-1, respectively, 2-3 orders of magnitude larger than those observed for highly magnetic S-state atoms. This is strong evidence for an additional, dominant, spin relaxation mechanism, electrostatic anisotropy, in collisions between these "submerged-shell" L > 0 atoms. These large spin relaxation rates imply that evaporative cooling of these atoms in a magnetic trap will be highly inefficient.Comment: 10 pages, 3 figure

    Analysis of Automated Emergency Braking System to Investigate Forward Collision Condition Using Scenario-Based Virtual Assessment

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    In the recent trend of automotive technologies, active safety systems for vehicles have become one ofthe key elements to reduce road traffic conditions. Automated vehicles are known as one of the active safetysystems to minimize road traffic congestion and unwanted road hazardous situations. Generally, automatedvehicles are designed using advanced driving assistance system (ADAS) technology to enhance the safetycapability of the vehicles. Moreover, automated vehicles are designed to adopt multiple scenarios with differenttypes of traffic situations. Generally, the performance of automated vehicles is evaluated to adapt with various roadconditions and different type of traffic conditions, autonomously. Nonetheless, most of the safety testing wasconducted in a controlled environment and with less traffic conditions. Moreover, this technology is tested indeveloped countries and mostly evaluated for highway driving scenarios, with less pedestrians and motorist’s roadusers. On the other hand, in developing countries such as Malaysia, most of the automotive researchers haveinitiated research related to automated vehicle based on controlled environment only. One of the primary focusesfor the current automotive researchers is to reduce road accidents due to frontal collision. Thus, automatedemergency braking systems have been heavily investigated by most developers to minimize road accidents. Mostof the researchers analyze the system in terms of theoretical based simulation and tested using actual vehicle forphysical testing. However, this type of testing is not sufficient to optimize the performance of automatedemergency braking systems for developing countries. Therefore, this study focuses on scenario-based virtualassessment to evaluate the capability of autonomous vehicles using automated emergency braking system withoutcausing road casualties with the distance range is 4.5m to 0.5m depending on vehicle speed. &nbsp

    Analysis of Automated Emergency Braking System to Investigate Forward Collision Condition Using Scenario-Based Virtual Assessment

    Get PDF
    In the recent trend of automotive technologies, active safety systems for vehicles have become one ofthe key elements to reduce road traffic conditions. Automated vehicles are known as one of the active safetysystems to minimize road traffic congestion and unwanted road hazardous situations. Generally, automatedvehicles are designed using advanced driving assistance system (ADAS) technology to enhance the safetycapability of the vehicles. Moreover, automated vehicles are designed to adopt multiple scenarios with differenttypes of traffic situations. Generally, the performance of automated vehicles is evaluated to adapt with various roadconditions and different type of traffic conditions, autonomously. Nonetheless, most of the safety testing wasconducted in a controlled environment and with less traffic conditions. Moreover, this technology is tested indeveloped countries and mostly evaluated for highway driving scenarios, with less pedestrians and motorist’s roadusers. On the other hand, in developing countries such as Malaysia, most of the automotive researchers haveinitiated research related to automated vehicle based on controlled environment only. One of the primary focusesfor the current automotive researchers is to reduce road accidents due to frontal collision. Thus, automatedemergency braking systems have been heavily investigated by most developers to minimize road accidents. Mostof the researchers analyze the system in terms of theoretical based simulation and tested using actual vehicle forphysical testing. However, this type of testing is not sufficient to optimize the performance of automatedemergency braking systems for developing countries. Therefore, this study focuses on scenario-based virtualassessment to evaluate the capability of autonomous vehicles using automated emergency braking system withoutcausing road casualties with the distance range is 4.5m to 0.5m depending on vehicle speed. &nbsp

    Targeting the LOX/hypoxia axis reverses many of the features that make pancreatic cancer deadly: inhibition of LOX abrogates metastasis and enhances drug efficacy

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    Pancreatic ductal adenocarcinoma (PDAC) is one of the leading causes of cancer‐related mortality. Despite significant advances made in the treatment of other cancers, current chemotherapies offer little survival benefit in this disease. Pancreaticoduodenectomy offers patients the possibility of a cure, but most will die of recurrent or metastatic disease. Hence, preventing metastatic disease in these patients would be of significant benefit. Using principal component analysis (PCA), we identified a LOX/hypoxia signature associated with poor patient survival in resectable patients. We found that LOX expression is upregulated in metastatic tumors from Pdx1‐Cre KrasG12D/+ Trp53R172H/+ (KPC) mice and that inhibition of LOX in these mice suppressed metastasis. Mechanistically, LOX inhibition suppressed both migration and invasion of KPC cells. LOX inhibition also synergized with gemcitabine to kill tumors and significantly prolonged tumor‐free survival in KPC mice with early‐stage tumors. This was associated with stromal alterations, including increased vasculature and decreased fibrillar collagen, and increased infiltration of macrophages and neutrophils into tumors. Therefore, LOX inhibition is able to reverse many of the features that make PDAC inherently refractory to conventional therapies and targeting LOX could improve outcome in surgically resectable disease

    The validity of using ICD-9 codes and pharmacy records to identify patients with chronic obstructive pulmonary disease

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    Background: Administrative data is often used to identify patients with chronic obstructive pulmonary disease (COPD), yet the validity of this approach is unclear. We sought to develop a predictive model utilizing administrative data to accurately identify patients with COPD. Methods: Sequential logistic regression models were constructed using 9573 patients with postbronchodilator spirometry at two Veterans Affairs medical centers (2003-2007). COPD was defined as: 1) FEV1/FVC <0.70, and 2) FEV1/FVC < lower limits of normal. Model inputs included age, outpatient or inpatient COPD-related ICD-9 codes, and the number of metered does inhalers (MDI) prescribed over the one year prior to and one year post spirometry. Model performance was assessed using standard criteria. Results: 4564 of 9573 patients (47.7%) had an FEV1/FVC < 0.70. The presence of ≥1 outpatient COPD visit had a sensitivity of 76% and specificity of 67%; the AUC was 0.75 (95% CI 0.74-0.76). Adding the use of albuterol MDI increased the AUC of this model to 0.76 (95% CI 0.75-0.77) while the addition of ipratropium bromide MDI increased the AUC to 0.77 (95% CI 0.76-0.78). The best performing model included: ≥6 albuterol MDI, ≥3 ipratropium MDI, ≥1 outpatient ICD-9 code, ≥1 inpatient ICD-9 code, and age, achieving an AUC of 0.79 (95% CI 0.78-0.80). Conclusion: Commonly used definitions of COPD in observational studies misclassify the majority of patients as having COPD. Using multiple diagnostic codes in combination with pharmacy data improves the ability to accurately identify patients with COPD.Department of Veterans Affairs, Health Services Research and Development (DHA), American Lung Association (CI- 51755-N) awarded to DHA, the American Thoracic Society Fellow Career Development AwardPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/84155/1/Cooke - ICD9 validity in COPD.pd
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