Probing helium interfaces with light scattering : from fluid mechanics to statistical physics

We have investigated the formation of helium droplets in two physical situations. In the first one, droplets are atomised from superfluid or normal liquid by a fast helium vapour flow. In the second, droplets of normal liquid are formed inside porous glasses during the process of helium condensation. The context, aims, and results of these experiments are reviewed, with focus on the specificity of light scattering by helium. In particular, we discuss how, for different reasons, the closeness to unity of the index of refraction of helium allows in both cases to minimise the problem of multiple scattering and obtain results which it would not be possible to get using other fluids.Comment: 21 page

D* Production in Deep Inelastic Scattering at HERA

This paper presents measurements of D^{*\pm} production in deep inelastic scattering from collisions between 27.5 GeV positrons and 820 GeV protons. The data have been taken with the ZEUS detector at HERA. The decay channel $D^{*+}\to (D^0 \to K^- \pi^+) \pi^+$ (+ c.c.) has been used in the study. The $e^+p$ cross section for inclusive D^{*\pm} production with $5<Q^2<100 GeV^2$ and $y<0.7$ is 5.3 \pms 1.0 \pms 0.8 nb in the kinematic region {$1.3<p_T(D^{*\pm})<9.0$ GeV and $| \eta(D^{*\pm}) |<1.5$}. Differential cross sections as functions of p_T(D^{*\pm}), $\eta(D^{*\pm}), W$ and $Q^2$ are compared with next-to-leading order QCD calculations based on the photon-gluon fusion production mechanism. After an extrapolation of the cross section to the full kinematic region in p_T(D^{*\pm}) and $\eta$(D^{*\pm}), the charm contribution $F_2^{c\bar{c}}(x,Q^2)$ to the proton structure function is determined for Bjorken $x$ between 2 $\cdot$ 10$^{-4}$ and 5 $\cdot$ 10$^{-3}$.Comment: 17 pages including 4 figure

Observation of Scaling Violations in Scaled Momentum Distributions at HERA

Charged particle production has been measured in deep inelastic scattering (DIS) events over a large range of $x$ and $Q^2$ using the ZEUS detector. The evolution of the scaled momentum, $x_p$, with $Q^2,$ in the range 10 to 1280 $GeV^2$, has been investigated in the current fragmentation region of the Breit frame. The results show clear evidence, in a single experiment, for scaling violations in scaled momenta as a function of $Q^2$.Comment: 21 pages including 4 figures, to be published in Physics Letters B. Two references adde

Regional variations in quality of survival among men with prostate cancer across the United Kingdom

Purpose: Prostate cancer incidence, treatment and survival rates vary throughout the United Kingdom (UK) but little is known about regional differences in quality of survival. Objective: To investigate variations in patient-reported outcomes between UK countries and English Cancer Alliances. Design, setting and participants: A cross-sectional postal survey of prostate cancer survivors diagnosed 18-42 months previously. Outcome measurements and statistical analysis: Urinary, bowel, sexual problems and vitality were patient reported using the EPIC-26 questionnaire. General health was also self-assessed. Regional variations were identified using multivariable log-linear regression. Results and limitations: 35,823 men responded; 60.8% of those invited. Self-assessed health was significantly lower than the UK average in Wales and Scotland. Respondents reported more urinary incontinence in Scotland, more urinary irritation/obstruction in Scotland and Northern Ireland (NI), poorer bowel function in Scotland and NI, worse sexual function in Scotland, and reduced vitality/hormonal function in Scotland, Wales and NI. Self-assessed health was poorer than the English average in South Yorkshire and North-East & Cumbria, with more urinary incontinence in North-East & Cumbria and Peninsula, greater sexual problems in West Midlands and poorer vitality in North-East & Cumbria and West Midlands. Limitations include difficulty identifying clinically significant differences and limited information on pre-treatment conditions. Conclusions: Despite adjustment for treatment, clinical and socio-demographic factors, quality of survival among prostate cancer survivors varied by area of residence. Adoption of best practice from areas performing well could support enhanced survival quality in poorer performing areas, particularly with regards bowel problems and vitality, where clinically relevant differences were reported. Patient summary: We conducted a UK-wide survey of patient’s quality of life after treatment for prostate cancer. Outcomes were found to vary depending upon where patients live. Different service providers need to ensure that all prostate cancer patients receive the same follow up care

Quality of life in men living with advanced and localised prostate cancer: A United Kingdom population-wide patient-reported outcome study of 30,000 men

Background. Little is known about the health-related quality of life (HRQL) of men living with advanced prostate cancer. We report population-wide functional outcomes and HRQL in men with all stages of prostate cancer, and identify implications for healthcare delivery. Methods. Men alive 18-42 months after diagnosis of prostate cancer were identified through cancer registration data. A postal survey was administered which contained validated measures to assess a) functional outcomes (EPIC-26 plus use of interventions for sexual dysfunction) and b) generic HRQL (EQ-5D-5L & self-assessed health). Log-linear and binary logistic regression models were used to compare functional outcomes and HRQL across diagnostic stage and self-reported treatment groups. Findings. 35,823 (60.8%) men responded. Stage was known for 85.8%; 19,599 (63.8%) stage I/II, 7,209 (23.4%) stage III, 3,925 (12.8%) stage IV. Functional outcomes: Poor sexual function was common (81.0%), regardless of stage, and over half of men (55.8%) received no intervention for this. Differences in urinary and bowel morbidity were greater with respect to treatment than stage. In men treated with androgen deprivation therapy (ADT), 30.7% reported moderate/big problems with hot flushes, 29.4% with lack of energy and 22.5% with weight gain. HRQL: Overall self-assessed health was similar in men with stage I-III disease, and whilst reduced in those with stage IV cancer, 23.5% with metastatic disease reported no problems on any EQ-5D dimension. Interpretation. Men diagnosed with advanced disease do not report markedly different HRQL outcomes to those diagnosed with localised disease, although substantial problems with hormonal function and fatigue are reported amongst men treated with ADT. Sexual dysfunction is common and the majority of men are not offered helpful intervention or support. Service improvements around sexual rehabilitation and measures to reduce the impact of ADT are required

Observation of Events with an Energetic Forward Neutron in Deep Inelastic Scattering at HERA

In deep inelastic neutral current scattering of positrons and protons at the center of mass energy of 300 GeV, we observe, with the ZEUS detector, events with a high energy neutron produced at very small scattering angles with respect to the proton direction. The events constitute a fixed fraction of the deep inelastic, neutral current event sample independent of Bjorken x and Q2 in the range 3 · 10-4 \u3c xBJ \u3c 6 · 10-3 and 10 \u3c Q2 \u3c 100 GeV2

Age-adjustment in experimental animal data and its application to lung cancer in radon-exposed rats

Procedures for age-adjustment of cancer fractions are proposed which do not require fixed age intervals. The full available information on survival times can then be used, which is especially important in small treatment groups. For incidental cancers a non-decreasing prevalence function and for fatal cancers the Kaplan-Meier estimator is used. In the latter case, the estimated competing risk of the control population is standardized, not its true survival. This makes the technique also applicable to treatment groups with high incidence, which otherwise may give adjusted rates above 100%. In the application part these age-adjustment techniques are used here to study lung cancer in radon-exposed Wistar and Sprague-Dawley rats. The data include a classification in fatal and incidental lung cancers. For fatal lung cancer, the lifetime excess absolute risk (LEAR) at 1 WLM averaged over all exposed groups is 0.67x10 -4 for the Wistar rats, while for the Sprague-Dawley rats it is 0.40x10-4. For the Sprague-Dawley rats, there are several groups exposed later in life. When the averaging is restricted to animals with start of exposure prior to 150 days of age, the weighted average risk among the Sprague-Dawley rats is 0.79x10-4. Compared to groups with similar exposures as young adults (up to about 150 days), animals exposed later in life have substantially lower lifetime risks. The Wistar rats include groups with roughly equal exposure rates and ages at start of exposure, but with increasing exposure duration. Within these groupings the LEAR at 1 WLM does not decrease with additional exposure at higher age, as would be expected if the risk from exposures at different ages would be additive. © Springer 2004