A Perfect Match Condition for Point-Set Matching Problems Using the Optimal Mass Transport Approach

We study the performance of optimal mass transport--based methods applied to point-set matching problems. The present study, which is based on the L2 mass transport cost, states that perfect matches always occur when the product of the point-set cardinality and the norm of the curl of the nonrigid deformation field does not exceed some constant. This analytic result is justified by a numerical study of matching two sets of pulmonary vascular tree branch points whose displacement is caused by the lung volume changes in the same human subject. The nearly perfect match performance verifies the effectiveness of this mass transport--based approach.Read More: http://epubs.siam.org/doi/abs/10.1137/12086443

Ventricular divergence correlates with epicardial wavebreaks and predicts ventricular arrhythmia in isolated rabbit hearts during therapeutic hypothermia

INTRODUCTION: High beat-to-beat morphological variation (divergence) on the ventricular electrogram during programmed ventricular stimulation (PVS) is associated with increased risk of ventricular fibrillation (VF), with unclear mechanisms. We hypothesized that ventricular divergence is associated with epicardial wavebreaks during PVS, and that it predicts VF occurrence. METHOD AND RESULTS: Langendorff-perfused rabbit hearts (n = 10) underwent 30-min therapeutic hypothermia (TH, 30°C), followed by a 20-min treatment with rotigaptide (300 nM), a gap junction modifier. VF inducibility was tested using burst ventricular pacing at the shortest pacing cycle length achieving 1:1 ventricular capture. Pseudo-ECG (p-ECG) and epicardial activation maps were simultaneously recorded for divergence and wavebreaks analysis, respectively. A total of 112 optical and p-ECG recordings (62 at TH, 50 at TH treated with rotigaptide) were analyzed. Adding rotigaptide reduced ventricular divergence, from 0.13±0.10 at TH to 0.09±0.07 (p = 0.018). Similarly, rotigaptide reduced the number of epicardial wavebreaks, from 0.59±0.73 at TH to 0.30±0.49 (p = 0.036). VF inducibility decreased, from 48±31% at TH to 22±32% after rotigaptide infusion (p = 0.032). Linear regression models showed that ventricular divergence correlated with epicardial wavebreaks during TH (p<0.001). CONCLUSION: Ventricular divergence correlated with, and might be predictive of epicardial wavebreaks during PVS at TH. Rotigaptide decreased both the ventricular divergence and epicardial wavebreaks, and reduced the probability of pacing-induced VF during TH

Synthesis of Polycyclic Aromatic Hydrocarbons by Phenyl Addition-Dehydrocyclization: The Third Way.

Polycyclic aromatic hydrocarbons (PAHs) represent the link between resonance-stabilized free radicals and carbonaceous nanoparticles generated in incomplete combustion processes and in circumstellar envelopes of carbon rich asymptotic giant branch (AGB) stars. Although these PAHs resemble building blocks of complex carbonaceous nanostructures, their fundamental formation mechanisms have remained elusive. By exploring these reaction mechanisms of the phenyl radical with biphenyl/naphthalene theoretically and experimentally, we provide compelling evidence on a novel phenyl-addition/dehydrocyclization (PAC) pathway leading to prototype PAHs: triphenylene and fluoranthene. PAC operates efficiently at high temperatures leading through rapid molecular mass growth processes to complex aromatic structures, which are difficult to synthesize by traditional pathways such as hydrogen-abstraction/acetylene-addition. The elucidation of the fundamental reactions leading to PAHs is necessary to facilitate an understanding of the origin and evolution of the molecular universe and of carbon in our galaxy

Changes in Immunological and Hematological Parameters of Female Residents Exposed to Volatile Organic Compounds in the City of Kaohsiung, Taiwan

The objective of this study was to assess the effects, if any, of volatile organic compounds (VOCs) in the ambient air of Kaohsiuug, Taiwan, on certain hematological and immunological parameters of 153 female study participants. The major source of VOCs was vehicle emissions. The participants were selected from three areas, each area at a different distance from a freeway. Results indicated that total concentrations of VOCs and a subgroup of 25 VOCs (VOC25.) ranged from 250 to 335 ppb and 89 to 113 ppb, respectively. The distribution of VOC concentrations did not correlate with distance from the freeway. The participants living in the area with higher VOC concentrations had significantly higher abnormalities of white blood cells (WBC) and hemoglobin (Hb). In addition, IgG and IgA counts were significantly lower for the participants in the area with higher VOCs than for participants in the area with lower VOCs. This finding indicates that VOCs in ambient air may suppress immunological variables

Headache in the Pediatric Emergency Service: A Medical Center Experience

BackgroundHeadache is a common complaint in children and is one of the most common reasons for presentation at a pediatric emergency department (PED). This study described the etiologies of patients with headache seen in the PED and determined predictors of intracranial pathology (ICP) requiring urgent intervention. A secondary objective was to develop rapid, practical tools for screening headache in the PED.MethodsWe conducted a retrospective chart review of children who presented with a chief complaint of headache at the PED during 2008. First, we identified possible red flags in the patients' history or physical examination and neurological examination findings. Then, we recorded the brain computed tomography results.ResultsDuring the study period, 43,913 visits were made to the PED; in 409 (0.9%) patients, the chief complaint was headache. Acute viral, respiratory, and febrile illnesses comprised the most frequent cause of headache (59.9%). Six children (1.5%) had life-threatening ICP findings. In comparison with the group without ICP, the group with ICP had a significantly higher percentage of blurred vision (p = 0.008) and ataxia (p = 0.002).ConclusionBlurred vision and ataxia are the best clinical parameters to predict ICP findings

Doxorubicin in Combination with a Small TGFβ Inhibitor: A Potential Novel Therapy for Metastatic Breast Cancer in Mouse Models

Recent studies suggested that induction of epithelial-mesenchymal transition (EMT) might confer both metastatic and self-renewal properties to breast tumor cells resulting in drug resistance and tumor recurrence. TGFbeta is a potent inducer of EMT and has been shown to promote tumor progression in various breast cancer cell and animal models.We report that chemotherapeutic drug doxorubicin activates TGFbeta signaling in human and murine breast cancer cells. Doxorubicin induced EMT, promoted invasion and enhanced generation of cells with stem cell phenotype in murine 4T1 breast cancer cells in vitro, which were significantly inhibited by a TGFbeta type I receptor kinase inhibitor (TbetaRI-KI). We investigated the potential synergistic anti-tumor activity of TbetaR1-KI in combination with doxorubicin in animal models of metastatic breast cancer. Combination of Doxorubicin and TbetaRI-KI enhanced the efficacy of doxorubicin in reducing tumor growth and lung metastasis in the 4T1 orthotopic xenograft model in comparison to single treatments. Doxorubicin treatment alone enhanced metastasis to lung in the human breast cancer MDA-MB-231 orthotopic xenograft model and metastasis to bone in the 4T1 orthotopic xenograft model, which was significantly blocked when TbetaR1-KI was administered in combination with doxorubicin.These observations suggest that the adverse activation of TGFbeta pathway by chemotherapeutics in the cancer cells together with elevated TGFbeta levels in tumor microenvironment may lead to EMT and generation of cancer stem cells resulting in the resistance to the chemotherapy. Our results indicate that the combination treatment of doxorubicin with a TGFbeta inhibitor has the potential to reduce the dose and consequently the toxic side-effects of doxorubicin, and improve its efficacy in the inhibition of breast cancer growth and metastasis

A Close Binary Star Resolved from Occultation by 87 Sylvia

The star BD+29 1748 was resolved to be a close binary from its occultation by the asteroid 87 Sylvia on 2006 December 18 UT. Four telescopes were used to observe this event at two sites separated by some 80 km apart. Two flux drops were observed at one site, whereas only one flux drop was detected at the other. From the long-term variation of Sylvia, we inferred the probable shape of the shadow during the occultation, and this in turn constrains the binary parameters: the two components of BD+29 1748 have a projected separation of 0.097" to 0.110" on the sky with a position angle 104 deg to 107 deg. The asteroid was clearly resolved with a size scale ranging from 130 to 290 km, as projected onto the occultation direction. No occultation was detected for either of the two known moonlets of 87 Sylvia.Comment: 12 pages, 4 figures, 2 tables; submitted to the PAS