Erratum: Hanbury Brown-Twiss Interferometry at a Free-Electron Laser [Phys. Rev. Lett. 111, 034802 (2013)].

This corrects the article DOI: 10.1103/PhysRevLett.111.034802.

Revealing Three-Dimensional Structure of an Individual Colloidal Crystal Grain by Coherent X-Ray Diffractive Imaging.

We present results of a coherent x-ray diffractive imaging experiment performed on a single colloidal crystal grain. The full three-dimensional (3D) reciprocal space map measured by an azimuthal rotational scan contained several orders of Bragg reflections together with the coherent interference signal between them. Applying the iterative phase retrieval approach, the 3D structure of the crystal grain was reconstructed and positions of individual colloidal particles were resolved. As a result, an exact stacking sequence of hexagonal close-packed layers including planar and linear defects were identified.

Single pulse coherence measurements in the water window at the free-electron laser FLASH.

The spatial coherence of free-electron laser radiation in the water window spectral range was studied, using the third harmonic (λ<(3rd) = 2.66 nm) of DESY's Free-electron LASer in Hamburg (FLASH). Coherent single pulse diffraction patterns of 1,2-Dioleoyl-sn-glycero-3-phosphocholine (DOPC) multilamellar lipid stacks have been recorded. The intensity histogram of the speckle pattern around the first lamellar Bragg peak, corresponding to the d = 5 nm periodicity of the stack, reveals an average number of transverse modes of M¯ = 3.0 of the 3rd harmonic. Using the lipid stack as a 'monochromator', pulse-to-pulse fluctuations in the third harmonic λ(3rd) have been determined to be 0.033 nm.

Hanbury Brown-Twiss interferometry at a free-electron laser.

We present measurements of second- and higher-order intensity correlation functions (so-called Hanbury Brown-Twiss experiment) performed at the free-electron laser (FEL) FLASH in the non-linear regime of its operation. We demonstrate the high transverse coherence properties of the FEL beam with a degree of transverse coherence of about 80% and degeneracy parameter of the order 10(9) that makes it similar to laser sources. Intensity correlation measurements in spatial and frequency domain gave an estimate of the FEL average pulse duration of 50 fs. Our measurements of the higher-order correlation functions indicate that FEL radiation obeys Gaussian statistics, which is characteristic to chaotic sources.

Effect evaluation of a self-management program for dutch workers with a chronic somatic disease: a randomized controlled trial.

PURPOSE: The objective of this study is to investigate the effect of a Self-Management Program for workers with a chronic disease. This program is based on the Chronic Disease Self-Management Program of Stanford University, modified for workers with a chronic somatic disease. METHODS: In a randomized controlled trial, the effectiveness of a Self-Management Program was evaluated. Participants were randomly assigned to the experimental group (n = 57) and the control group (n = 47). The experimental group received an intervention, the control group received care as usual. Primary outcome measures were self-efficacy at work and the attitude towards self-management at work. Secondary outcomes were the SF-12 health survey questionnaire, job satisfaction and intention to change job. The results were measured at baseline, after the intervention and 8 months after the intervention. RESULTS: The attitude towards self-management at work (enjoyment) improved after 8 months for the intervention group (p = 0.030). No other outcome variable differed significantly. As an interaction effect, it was found that low educated workers developed a better physical health quality (SF-12) in the intervention group compared with the control group. The attitude towards self-management at work (importance) improved in the intervention group for older and female workers and the attitude toward enjoying self-management at work improved for female workers only. CONCLUSION: The results show that low educated workers, older workers and women benefit significantly more from the training than higher educated workers, younger workers and men.

Three-dimensional structure of a single colloidal crystal grain studied by coherent x-ray diffraction.

A coherent x-ray diffraction experiment was performed on an isolated colloidal crystal grain at the coherence beamline P10 at PETRA III. Using azimuthal rotation scans the three-dimensional (3D) scattered intensity from the sample in the far-field was measured. It includes several Bragg peaks as well as the coherent interference around these peaks. The analysis of the scattered intensity reveals the presence of plane defects in a single grain of the colloidal sample. We confirm these findings by model simulations. In these simulations we also analyze the experimental conditions required to phase the 3D diffraction pattern from a single colloidal grain. This approach has the potential to produce a high resolution image of the sample revealing its inner structure, with possible structural defects.

Spatial and temporal coherence properties of single free-electron laser pulses.

The experimental characterization of the spatial and temporal coherence properties of the free-electron laser in Hamburg (FLASH) at a wavelength of 8.0 nm is presented. Double pinhole diffraction patterns of single femtosecond pulses focused to a size of about 10×10 µm(2) were measured. A transverse coherence length of 6.2 ± 0.9 µm in the horizontal and 8.7 ± 1.0 µm in the vertical direction was determined from the most coherent pulses. Using a split and delay unit the coherence time of the pulses produced in the same operation conditions of FLASH was measured to be 1.75 ± 0.01 fs. From our experiment we estimated the degeneracy parameter of the FLASH beam to be on the order of 10(10) to 10(11), which exceeds the values of this parameter at any other source in the same energy range by many orders of magnitude.

"My lung disease won't go away, it's there to stay": profiles of adaptation to functional limitations in workers with asthma and COPD.

PURPOSE: Earlier research has shown that adaptation (i.e., the way in which employees cope with limitations resulting from their disease) is associated with sick leave. Our aim was to investigate signs of adequate or inadequate adaptation in employees with asthma and COPD. METHODS: A Q-methodological study was carried out among 34 workers with asthma or COPD. RESULTS: Four adaptation profiles were distinguished: the eager, the adjusted, the cautious, and the worried workers. The adaptation profiles provide insight into the different ways in which workers with asthma and COPD cope with their illness at work. CONCLUSIONS: The adaptation profiles serve as a starting point for the design of appropriate (occupational) care. The eager workers experience little difficulties at work; the cautious workers may need assistance in learning how to accept their disease; the worried workers need reassurance, and may need reactivation; the adjusted workers deserve extra attention, and, when necessary, advice on how to live with their asthma or COPD.

Occupational health and general practice: from opportunities lost to opportunities capitalised?

BACKGROUND AND AIM: Western populations are in the middle of the epidemiological transition of chronic diseases. Care of patients with chronic disease is directed at optimising life expectancy and quality of life. Daily and social functioning, including paid work are part of the treatment objectives. Yet, advice for and support in work related coping with chronic diseases, and collaboration with occupational health are not--yet--part of routine curative medical care procedures. This is also the case in general practice, where most patients with chronic conditions are treated. This 'blind spot' signals a generic lost opportunity in optimizing the care of patients with chronic disease. This paper analyses from empirical data the importance of integrating work-related advice and support in general practice and explores potential evidence of the benefits this provides for patients: the opportunities that can be capitalised through better interaction between occupational physicians (OP) and general practitioners (GP). METHODS: The paper is based on a review of three sources: (i) Epidemiology of chronic diseases: the Nijmegen Continuous Morbidity Registration; (ii) The relevant guidelines of the Dutch College of General Practitioners; (iii) Studies of work-related implications of asthma and COPD management of GPs of the Nijmegen centre of Evidence-Based Practice. RESULTS: Chronic diseases like cardiovascular disease, diabetes mellitus, COPD and asthma dominate general practice and lead annually to a large number of consultations. Although a majority of patients are 65 years or older--in particular for the first three diseases--GPs also care for a substantial number of under-65 years old. General practice guidelines for these disorders advocate care directed at normal functioning but do not systematically address functioning in the working place. Analysis of work-related functioning in case of chronic respiratory diseases, however, highlight that work-related factors and circumstances play an important role in patients' coping strategies. Patients tend to ignore negative effects of their workplace on their physical condition and as a consequence suffer undue limitations. Despite these work related risks, COPD patients who were in paid employement perceived higher quality of life than COPD patients who were disabled for work, but had similar disease severity (airway obstruction). Interestingly, a programme of patients' self-management of asthma resulted, in comparison to GP-supervised usual care in a substantial and lasting reduction of asthma related absence from work and other social-daily activities. CONCLUSIONS AND DISCUSSION: All consultations with employees with a chronic (respiratory) disease can be considered as opportunities to supervise work-related implications of the disease. Patients value their ability to work but frequently apply inefficient coping through ignoring the implications of their circumstances for their disease. A more efficient coping can probably be achieved through a more active involvement of patients in managing their own disease. Guidelines--like the Dutch College of General Practitioners'--have developed into a sophisticated and generally respected system of guidance of patient care. Explicit emphasis of management in relation to the workplace may present a logical opportunity to capitalise on.

Longitudinal changes in bronchial responsiveness associated with swine confinement dust exposure.

STUDY OBJECTIVES: Acute exposure to the air in swine confinement units causes bronchial hyperresponsiveness and inflammation of the airways. This study was performed to assess the longitudinal development of bronchial responsiveness in pig farmers and to establish exposure-response relationships. METHODS: A cohort of 171 pig farmers was followed over a 3-year period. Bronchial responsiveness was assessed by a histamine provocation test. Long-term average exposure to inhalable dust and endotoxin was determined by personal monitoring in summer and winter, using data on farm characteristics and activities. Time-weighted average (TWA) personal exposure to ammonia was measured. Data on farm characteristics were gathered in the same period. RESULTS: Mean increase in responsiveness was 2.52 doubling concentrations of histamine for a 10% decrease in FEV(1) and 1.36 doubling concentrations for a 20% decrease in FEV(1). Long-term average exposure to dust was 2.63 mg/m(3) and to endotoxin was 105 ng/m(3). TWA exposure to ammonia was 1.60 mg/m(3). After adjusting for age and smoking behavior, long-term average exposure to inhalable dust was associated with increases in bronchial responsiveness expressed as steps for provocative concentration causing 10% fall in FEV(1). TWA exposure to ammonia, use of wood shavings as bedding, and automated dry feeding were associated with increases in responsiveness expressed as steps for provocative concentration causing a 20% fall in FEV(1). CONCLUSIONS: Exposure to dust and ammonia in pig farms contributes to chronic inflammation of the airways and should be reduced.

Repeatability of self-reported data on occupational exposure to particular compounds.

The repeatability of self-reported occupational exposure to eight particular compounds was investigated in 209 males aged 49-87 years. The subjects completed an initial mailed questionnaire and were interviewed by telephone 3-5 weeks later. The study was carried out as part of a case-referent study on the relation between occupation and prostate cancer. The repeatability of answers was found to be better in the case of some agents than in that of others: kappas calculated as a measure of concordance range from 0.36 to 0.70. No substantial influence was found to be exercised by age or socioeconomic status, or by case or referent status. Although the repeatability observed was not flawless, it was concluded that self-reported exposure data would appear to be a sound basis for epidemiological studies on the aetiology of disease, whenever objective information on occupational exposure is not available.

Longitudinal changes in lung function associated with aspects of swine-confinement exposure.

Several aspects of swine-confinement farming appear to be leading to adverse respiratory effects. This study was set up in a longitudinal design to study the association between certain characteristics of farms or the way they are run and a decline in lung function. A cohort of 171 pig farmers was observed for 3 years. Lung function was measured. Exposure to farm characteristics was determined at the start of the observation period, using data from standardized farm surveys and from diaries kept by the participants. Mean decline in lung function was 73 mL/year for forced expiratory volume in 1 second (FEV1) and 55 mL/year for forced vital capacity (FVC). A longitudinal decline in FEV1 was significantly associated with the use of quaternary ammonium compounds as disinfectants (an additional 43 mL/year) and also with the use of an automated dry feeding system (an additional 28 mL/year). The association with the use of wood shavings as bedding material was not statistically significant. The impact of these characteristics in a longitudinal study provides stronger evidence for causal inference than that shown in previous cross-sectional designs. This may be useful in promoting preventive measures.

A simple method to evaluate the reliability of OWAS observations.

Slides showing nurses in different working postures were used to determine the reliability of OWAS observations. Each slide could be looked at for 3 seconds, while a new slide was shown every 30 seconds to resemble the normal practice of observation. Two observers twice scored a series of slides, some of them being identical at both viewings. To reduce effects of recall there was a time interval of 4 weeks or more between the two viewings and the slides were in a different order the second time. Different series were used to evaluate inter- and intra-observer reliability. The OWAS scores of corresponding slides were compared. In almost all comparisons percentages of agreement over 85% and kappa's over 0.6 were found, which is considered as good agreement. The procedure described seems to be a useful and simple technique to determine such reliability.

[Illness due to work or to an overactive thyroid?]. / Ziek door het werk of een te hard werkende schildklier?

An incapacity to work brought about by stress was diagnosed in two women aged 40 and 38. They were both in conflict situations at work and had psychological problems. They stopped working but remained tired and irritable. After being unfit for work for more than a year they were diagnosed with hyperthyroidism which was treated appropriately. They both recovered and resumed work. Hyperthyroidism can impair physical and mental functioning. Presenting symptoms may be confusing, specifically if work-related factors appear to be the obvious implication. In The Netherlands, employees who become ill, consult their general practitioner or a medical specialist, who are concerned with diagnosis and treatment. They also report to their employer's occupational-health department, where the physician focuses on work-related factors that may impair health and on assessment of disability. Communication between all parties should be optimal.