Gravitational compression of colloidal gels

We study the compression of depletion gels under the influence of a gravitational stress by monitoring the time evolution of the gel interface and the local volume fraction, φ, inside the gel. We find φ is not constant throughout the gel. Instead, there is a volume fraction gradient that develops and grows along the gel height as the compression process proceeds. Our results are correctly described by a non-linear poroelastic model that explicitly incorporates the φ-dependence of the gravitational, elastic and viscous stresses acting on the gel.

A potential serum panel for breast cancer diagnosis: ongoing clinical validation for its clinical implication

Abstract #5006

Although every effort has been made to discover single potent biomarkers in oncology, the promising single biomarker often loses its clinical potency in the course of clinical validations. We aimed to construct and verify a biomarker panel with multiple proteins for breast cancer diagnosis. Using Surface-Enhanced Laser Desorption/ Ionization Time-of-Flight mass spectrometry (SELDI-TOF-MS) and microbead array system, epidermal growth factor (EGF), vascular cell adhesion molecule-1 (VCAM-1), CD40L, vitronectin, plasminogen activation inhibitor-1 (PAI-1), vitamin-D binding protein (VDBP), C-reactive protein (CRP), kininogen, apolipoprotein A1 and proapolipoprotein A1 were identified and validated as useful biomarkers for detection of breast cancer. The multiplexing panel (MP) which was constructed by combining algorithm (random forest, support vector machine) with above biomarkers showed that the diagnostic accuracy approached 91% in 216 test samples. A following double blind test verified that the diagnostic accuracy of the MP was 68% with an additional validation set including sera from 49 patients with breast cancer and 51 healthy women (sensitivity=74%; 95% confidence interval (CI)=58.9–85.0%, specificity=62.7%; 95% CI=48.1–75.9%, positive predictive value=65.5%; 95% CI=55.7-75.3%, negative predictive value=71.7%; 95% CI=61.7-80.35%). We suggest that these results support the potential use of the MP as an early detector of breast cancer. In order to validate the role and potency of the MP in routine clinical practice, a large scale clinical validation in a cohort consisting of 500 patients with breast cancer and the same number of healthy women are underway and the results will be released in the near future.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 5006.

Evaluation of microtubule associated protein tau expression as prognostic and predictive marker in the NSABP-B 28 randomized clinical trial

Abstract #54

Objective: We assessed Tau protein expression in patients who participated in the National Surgical Breast and Bowel Project (NSABP)-B28 clinical trial using immunohistochemistry. Expression levels were correlated with disease-free (DFS) and overall survival (OS) and we also examined if there is interaction between this marker and paclitaxel efficacy. Patients and Methods: Tissue microarrays were available for 1942 patients (63 % of all trial participants) who were included in the NSABP-B28 clinical trial and were randomized to receive either 4 courses of doxorubicin/cyclophosphamide (AC) or AC followed by 4 additional courses of paclitaxel (ACT) adjuvant chemotherapy. All patients with hormone receptor positive tumors also received adjuvant endocrine treatment. Immunohistochemistry for Tau was performed at MD Anderson Cancer Center blinded to clinical outcome. Correlation with survival was performed by the NSABP Statistical Center. Results: Forty-three percent of tumors were Tau-positive defined as equal or greateer staining than in normal breast epithelium. Tau expression correlated strongly with estrogen receptor (ER)-positive status (p<0.0001). In univariate analyses, Tau, ER and HER-2 expression as well as grade, tumor size and nodal status were each independently and significantly associated with DFS and OS (p<0.003). In multivariate analysis, the same variables except HER2 remained significant. However, there was no significant interaction between Tau expression and benefit from paclitaxel in the entire population or among the ER-positive or ER-negative subsets, respectively. Conclusion: High Tau protein expression is associated with better prognosis including longer disease-free and overall survival in patients treated with adjuvant anthracyline and paclitaxel chemotherapy and endocrine therapy. However, we could not detect a statistically significant interaction between Tau expression and paclitaxel benefit.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 54.

Evaluation of microbial fuel cell coupled with aeration chamber and bio-cathode for organic matter and nitrogen removal from synthetic domestic wastewater

For simultaneous carbon and nitrogen removal via single stream, a microbial fuel cell (MFC) coupled with an aeration chamber and a bio-cathode was investigated. Without catalysts and any additional buffer, the MFC produced electricity continuously and the power density reached 1.3 W/m3 at a loading rate of 1.6 kg COD/m3 d. Simultaneously, the COD and the nitrate removal rate were 1.4 kg COD/m3 d and 67 g NO3-N/m3 d, respectively. When the hydraulic retention time was changed from 6 to 0.75 hours, the power density significantly increased from 0.2 to 10.8 W/m3 due to an increase of cathodic potential. When the aeration chamber was removed and the nitrate was injected into the cathode, the power density increased to 3.7 W/m3. At a high recirculation rate of 10 ml/min, the power density and the nitrate removal rate greatly increased to 34 W/m3 and 294 g NO3--N/m3 d, respectively.

Model-based evaluation of control strategies for phosphorus removal in a full-scale advanced phase isolation ditch process

A model-based evaluation of operation conditions and control strategies was conducted for phosphorus removal in a full-scale Advanced Phase Isolation Ditch (APID) process. The APID process is an alternating type and does not have a separated anaerobic reactor. We suggested that it would be a suitable operational option for robust phosphorus removal by having a different input point for the influent and return sludge flow at specific modes. For evaluation of control strategies, three cases of influent disturbance were assumed, and five manipulated variables were selected for controlling the cases of disturbance. In the case of an increased influent flow rate, a combination of four manipulated variables is proposed through our simulation results as the best control strategy. The optimal k(L)a value was found to be 250/d when pollutants loading kept increasing without variations in the flow rate. When both the pollutants loading and the influent flow rates were increased simultaneously, the robust control strategy is to combine the return sludge inflow point, the exclusive operation modes which have a relatively long hydraulic retention time (HRT), operation period of 30 minutes, and the increase of the return sludge flow rate in proportion to the influent flow rate added to 300/d of k(L)a value.

Search for gravitational-wave bursts from soft gamma repeaters

We present a LIGO search for short-duration gravitational waves (GWs) associated with soft gamma ray repeater (SGR) bursts. This is the first search sensitive to neutron star f modes, usually considered the most efficient GW emitting modes. We find no evidence of GWs associated with any SGR burst in a sample consisting of the 27 Dec. 2004 giant flare from SGR 1806-20 and 190 lesser events from SGR 1806-20 and SGR 1900+14. The unprecedented sensitivity of the detectors allows us to set the most stringent limits on transient GW amplitudes published to date. We find upper limit estimates on the model-dependent isotropic GW emission energies (at a nominal distance of 10 kpc) between 3x10;{45} and 9x10;{52} erg depending on waveform type, detector antenna factors and noise characteristics at the time of the burst. These upper limits are within the theoretically predicted range of some SGR models.

[Pulmonary schwannoma with hypervascularity; report of a case]

A 54-year-old female was admitted to our hospital with a mass shadow in the right pulmonary hilum. The chest computed tomography (CT) scan revealed a well-circumscribed mass in the lower lobe of the right lung. Bronchoscopic examination showed a submucosal tumor in the right basal bronchus which bled easily, and the angiogram showed a tumor with hypervascularity. The tumor was suspected to be a sclerosing hemangioma or malignant tumor. A right basal segmentectomy was performed, and the pathological diagnosis was that of schwannoma. During the 8 year follow-up period, she exhibited no evidence of recurrence.

Nifedipine encapsulated core-shell type nanoparticles based on poly(γ-benzyl L-glutamate)/poly(ethylene glycol) diblock copolymers

The diblock copolymers based on PBLG and PEO (GE) were synthesized and characterized. Nanoparticles showed spherical shape from the observations of TEM and approved core-shell structure. Drug contents were increased with use of higher initial drug concentration and higher Mw of GE. Nifedipine (NFD) release rate was slower in longer PBLG chain length and higher NFD contents than short PBLG chain length and lower drug contents of NFD due to the hydrophobic interaction between PBLG domain and NFD.

Angle-resolved photoemission spectroscopy of electron-doped cuprate superconductors: isotropic electron-phonon coupling

We have performed high resolution angle-resolved photoemission (ARPES) studies on electron-doped cuprate superconductors Sm2-xCexCuO4 (x=0.10, 0.15, 0.18), Nd2-xCexCuO4 (x=0.15), and Eu2-xCexCuO4 (x=0.15). Imaginary parts of the electron removal self energy show steplike features due to an electron-bosonic mode coupling. The steplike feature is seen along both nodal and antinodal directions but at energies of 50 and 70 meV, respectively, independent of the doping and rare earth element. Such energy scales can be understood as being due to preferential coupling to half- and full-breathing mode phonons, revealing the phononic origin of the kink structures. Estimated electron-phonon coupling constant lambda from the self energy is roughly independent of the doping and momentum. The isotropic nature of lambda is discussed in comparison with the hole-doped case where a strong anisotropy exists.

Novel Jeff=1/2 Mott state induced by relativistic spin-orbit coupling in Sr2IrO4

We investigated the electronic structure of 5d transition-metal oxide Sr2IrO4 using angle-resolved photoemission, optical conductivity, x-ray absorption measurements, and first-principles band calculations. The system was found to be well described by novel effective total angular momentum Jeff states, in which the relativistic spin-orbit coupling is fully taken into account under a large crystal field. Despite delocalized Ir 5d states, the Jeff states form such narrow bands that even a small correlation energy leads to the Jeff=1/2 Mott ground state with unique electronic and magnetic behaviors, suggesting a new class of Jeff quantum spin driven correlated-electron phenomena.