Flow boiling heat transfer and pressure drop of propane in smooth horizontal minichannels

Paper presented at the 5th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, South Africa, 1-4 July, 2007.This study examined convective boiling heat transfer and pressure drop in horizontal minichannels using propane. The local heat transfer coefficients and pressure drop were obtained for heat fluxes ranging from 5-20 kW m-2, mass fluxes ranging from 50-400 kg m-2 s-1, saturation temperatures of 10, 5, and 0°C, and quality up to 1.0. The test section was made of stainless steel tubes with inner diameters of 1.5 mm and 3.0 mm, and lengths of 1000 mm and 2000 mm, respectively. The section was heated uniformly by applying an electric current to the tubes directly. The present study showed an effect of mass flux, heat flux, inner tube diameter, and saturation temperature on heat transfer coefficient and pressure drop. The experimental results were compared against several two-phase heat transfer coefficient and pressure drop prediction methods. A new boiling heat transfer coefficient correlation based on the superposition model for propane in minichannels was developed with a mean deviation of 8.27%

In vivo impact of a 4 bp deletion mutation in the DLX3 gene on bone development

AbstractDistal-less 3 (DLX3) gene mutations are etiologic for Tricho-Dento-Osseous syndrome. To investigate the in vivo impact of mutant DLX3 on bone development, we established transgenic (TG) mice expressing the c.571_574delGGGG DLX-3 gene mutation (MT-DLX3) driven by a mouse 2.3 Col1A1 promoter. Microcomputed tomographic analyses demonstrated markedly increased trabecular bone volume and bone mineral density in femora from TG mice. In ex vivo experiments, TG mice showed enhanced differentiation of bone marrow stromal cells to osteoblasts and increased expression levels of bone formation markers. However, TG mice did not show enhanced dynamic bone formation rates in in vivo fluorochrome double labeling experiments. Osteoclastic differentiation capacities of bone marrow monocytes were reduced in TG mice in the presence of osteoclastogenic factors and the numbers of TRAP(+) osteoclasts on distal metaphyseal trabecular bone surfaces were significantly decreased. TRACP 5b and CTX serum levels were significantly decreased in TG mice, while IFN-γ levels were significantly increased. These data demonstrate that increased levels of IFN-γ decrease osteoclast bone resorption activities, contributing to the enhanced trabecular bone volume and mineral density in these TG mice. These data suggest a novel role for this DLX-3 mutation in osteoclast differentiation and bone resorption

Supernova Bounds on Majoron-emitting decays of light neutrinos

Neutrino masses arising from the spontaneous violation of ungauged lepton-number are accompanied by a physical Goldstone boson, generically called Majoron. In the high-density supernova medium the effects of Majoron-emitting neutrino decays are important even if they are suppressed in vacuo by small neutrino masses and/or small off-diagonal couplings. We reconsider the influence of these decays on the neutrino signal of supernovae in the light of recent Super-Kamiokande data on solar and atmospheric neutrinos. We find that majoron-neutrino coupling constants in the range 3\times 10^{-7}\lsim g\lsim 2\times 10^{-5} or g \gsim 3 \times 10^{-4} are excluded by the observation of SN1987A. Then we discuss the potential of Superkamiokande and the Sudbury Neutrino Observatory to detect majoron neutrino interactions in the case of a future galactic supernova. We find that these experiments could probe majoron neutrino interactions with improved sensitivity.Comment: 28 pages, 5 figure

Universal scaling of the Hall resistivity in MgB2 superconductors

The mixed-state Hall resistivity and the longitudinal resistivity in superconducting MgB2 thin films have been investigated as a function of the magnetic field over a wide range of current densities from 100 to 10000 A/cm^2. We observe a universal Hall scaling behavior with a constant exponent of 2.0, which is independent of the magnetic field, the temperature, and the current density. This result can be interpreted well within the context of recent theories.Comment: 4 page

Financial toxicity in adults with cancer: Adverse outcomes and noncompliance

Purpose Because of the escalating cost of cancer care coupled with high insurance deductibles, premiums, and uninsured populations, patients with cancer are affected by treatmentrelated financial harm, known as financial toxicity. The purpose of this study was to describe individuals reporting financial toxicity and to identify rates of and reasons for affordability-related treatment noncompliance. Methods From May 2010 to November 2015, adult patients (age $ 18 years) with cancer were identified from a Health Registry/Cancer Survivorship Cohort. Financial toxicity was defined as agreement with the phrase"You have to pay for more medical care than you can afford" from the Patient Satisfaction Questionnaire-18. Logistic regression and Fisher exact tests were used to compare groups. Results Of 1,988 participants, 524 (26%) reported financial toxicity. Patients reporting financial toxicity were more likely age 65 years or younger, female, nonwhite, non-English speaking, not married, less educated, and to have received a diagnosis more recently (all P,.001). Participants with financial toxicity were more likely to report noncompliance with medication, owing to inability to afford prescription drugs (relative risk [RR], 3.55; 95% CI, 2.53 to 4.98), and reported forgoing mental health care (RR, 3.89; 95% CI, 2.04 to 7.45), doctor's visits (RR, 2.98; 95% CI, 1.97 to 4.51), and medical tests (RR, 2.54; 95% CI, 1.49 to 4.34). The most endorsed reasons for delayed care were not having insurance coverage and being unable to afford household expenses. Conclusion More than25%of adultswith cancer reportedfinancial toxicity thatwas associatedwith an increased riskfor medicalnoncompliance.Financial toxicity remains a major issue in cancer care, and efforts are needed to ensure patients experiencing high levels offinancial toxicity are able to access recommended care

Four Light Neutrinos in Singular Seesaw Mechanism with Abelian Flavor Symmetry

The four light neutrino scenario, which explains the atmosphere, solar and LSND neutrino experiments, is studied in the framework of the seesaw mechanism. By taking both the Dirac and Majorana mass matrix of neutrinos to be singular, the four neutrino mass spectrum consisting of two almost degenerate pairs separated by a mass gap $\sim 1$ eV is naturally generated. Moreover the right-handed neutrino Majorana mass can be at $\sim 10^{14}$ GeV scale unlike in the usual singular seesaw mechanism. Abelian flavor symmetry is used to produce the required neutrino mass pattern. A specific example of the flavor charge assignment is provided to show that maximal mixings between the $\nu_\mu-\nu_\tau$ and $\nu_e-\nu_s$ are respectively attributed to the atmosphere and solar neutrino anomalies while small mixing between two pairs to the LSND results. The implication in the other fermion masses is also discussed.Comment: Firnal version to appear in PR

Weight gain in hormone receptor-positive (HR+) early-stage breast cancer: is it menopausal status or something else?

Purpose: This study investigates weight trajectories in pre- versus postmenopausal breast cancer (BC) survivors diagnosed with hormone receptor-positive tumors, with a specific focus on discerning menopausal status and type of endocrine treatment (ET) as risk factors for weight gain during ET. Methods: We conducted a retrospective review of electronic medical records. Descriptive statistics and Chi-squared and t tests were used to compare pre- and postmenopausal women. Chi-squared tests and ANOVA were used for within-group associations between patient characteristics and weight trajectories. Log-binomial regression models were used to estimate relative risk for weight gain. Results: The final sample was 32% premenopausal (n = 140) and 68% postmenopausal (n = 298). Relative risk (RR) for weight gain during ET was highest in women who were premenopausal (RR = 1.29, 1.03–1.52) and had Stage 3 BC (RR = 2.12, 1.59–2.82), mastectomy (RR = 1.49, 1.19–1.88), axillary node dissection (RR = 1.39, 1.11–1.73), and chemotherapy (RR = 1.80, 1.37–2.36). For each kg of weight gained between BC diagnosis and start of ET, and for each additional year of age, RR of gaining weight during ET decreased (RR = 0.98, 0.97–0.99, and RR = 0.99, 0.98–0.99, respectively). Menopausal status and type of ET were not significant predictors of weight gain. In multivariable analysis, only weight loss between BC diagnosis and start of ET was significant. Conclusion: The association of weight loss prior to ET and subsequent substantial weight gain during ET warrants further investigation

Pseudogap formation of four-layer BaRuO3_3 and its electrodynamic response changes

We investiaged the optical properties of four-layer BaRuO$_{3}$, which shows a fermi-liquid-like behavior at low temperature. Its optical conductivity spectra clearly displayed the formation of a pseudogap and the development of a coherent peak with decreasing temperature. Temperature-dependences of the density $n$ and the scattering rate $1/\tau$ of the coherent component were also derived. As the temperature decreases, both $n$ and $1/\tau$ decrease for four-layer BaRuO$_{3}$. These electrodynamic responses were compared with those of nine-layer BaRuO$_{3}$, which also shows a pseudogap formation but has an insulator-like state at low temperature. It was found that the relative rates of change of both $n$ and $1/\tau$ determine either metallic or insulator-like responses in the ruthenates. The optical properties of the four-layer ruthenate were also compared with those of other pseudogap systems, such as high $T_{c}$ cuprates and heavy electron systems.Comment: 7 figures. submitted to Phys. Rev.

A system for investigating oesophageal photoplethysmographic signals in anaesthetised patients

The monitoring of arterial blood oxygen saturation in patients with compromised peripheral perfusion is often difficult, because conventional non-invasive techniques such as pulse oximetry (SpO2) can fail. Poor peripheral circulation commonly occurs after major surgery including cardiopulmonary bypass. The difficulties in these clinical situations might be overcome if the sensor were to monitor a better perfused central part of the body such as the oesophagus. A new oesophageal photoplethysmographic (PPG) probe and an isolated processing system have been developed to investigate the pulsatile signals of anaesthetised adult patients undergoing routine surgery. Measurements were made in the middle third of the oesophagus, 25 cm to 30 cm from the upper incisors. The AC PPG signals are sampled by a data acquisition system connected to a laptop computer. The signals recorded correspond to infrared and red AC PPGs from the middle third oesophagus and the finger. Preliminary results from 20 patients show that good quality AC PPG signals can be measured in the human oesophagus. The ratio of the oesophageal to finger AC PPG amplitudes was calculated for the infrared and red wavelengths for each patient. The mean (+/- standard deviation) of this ratio was 2.9 +/- 2.1 (n = 19) for the infrared wavelength and 3.1 +/- 2.4 (n = 16) for the red wavelength. The red and infrared wavelengths used are appropriate for pulse oximetry and this investigation indicates that the mid-oesophagus may be a suitable site for the reliable monitoring of SpO2 in patients with poor peripheral perfusion

Weight changes in postmenopausal breast cancer survivors over 2 years of endocrine therapy: a retrospective chart review

Purpose: Obesity and weight gain after breast cancer (BC) diagnosis can affect cancer outcomes. This study explores the question of weight change during the first 2 years of endocrine treatment (ET) to identify the independent effects of BC diagnosis and treatment on post-diagnosis weight trajectories in early-stage postmenopausal BC survivors. Methods: The study design is a retrospective chart review. Chi square tests and ANOVA were used to compare patients who gained >2 kg, lost >2 kg, or had stable weight. Log-binomial regression models were used to evaluate associations between patient characteristics and weight trajectories. Results: The final sample is N = 300, with mean age at BC diagnosis of 65 years and 76% white. After 2 years of ET, 39% of study participants had gained >2 kg, 27% had lost >2 kg, and 34% had stable weight. Relative risks (RR) for weight gain were as follows: age at diagnosis = 0.98 (0.96, 0.99), being married = 1.48 (1.04, 2.12), weight change between BC diagnosis and start of ET = 0.98 (0.97, 0.99), Stage II = 1.42 (1.01, 2.01) or Stage III = 1.99 (1.41, 2.82), PR negative = 0.70 (0.51, 0.96), HER2 positive = 1.51 (1.07, 2.13), mastectomy = 1.49 (1.12, 1.98), axillary node dissection = 1.67 (1.27, 2.20), adjuvant chemotherapy = 1.49 (1.02, 2.19), and neoadjuvant chemotherapy = 2.29 (1.67, 3.14). Type of ET (tamoxifen or aromatase inhibitor) was not significant. Conclusions: In our sample of postmenopausal early-stage BC survivors, a majority had stable or lost weight during the first 2 years of ET. Higher disease complexity and associated treatment posed higher RR for weight gain