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The evaluation of writing is challenging for foreign language teachers in many different regards. Different evaluation methods have frequently been the topic of writing research, but the reliability of different evaluation methods has rarely been studied side-to-side. This study aimed to analyse the inter- and intra- rater reliability in an EFL context of three different evaluation methods: holistic, analytic, and relative evaluation. Four secondary school teachers were selected to rate twenty different written products by beginner and advanced EFL students, using every evaluation method once for every written product. Raters used an adapted version of the ESL Composition Profile for analytic evaluation, and one reference text for relative evalution. Results indicated a high degree of agreement between raters and great internal consistency for individual raters, showcasing differences between L1 and L2 writing evaluation procedures. However, no significant effects were found for differences between correlation coefficients of different evaluation methods. The reliability of individual raters and the reliability across multiple raters was not affected significantly by the evaluation method. Various explanations for these findings are discussed, together with classroom implications and recommendations for further writing studies on the reliability of evaluation methods.

De inzet van peerfeedback heeft als voordeel dat het de werkdruk van docenten verlaagt en dat de schrijfvaardigheid van leerlingen verbetert doordat ze leren van het beoordelen van elkaars werk. Een voorwaarde is wel dat leerlingen weten waarop je feedback geeft, hoe je feedback verwoordt en hoe je feedback verwerkt. De resultaten van dit onderzoek tonen aan dat de feedbackkwaliteit van leerlingen significant verbetert wanneer zij deze vaardigheden aangeleerd krijgen middels expliciete feedbackinstructie. Daarnaast wordt de schrijfvaardigheid van de leerlingen uit de experimentele klas significant beter als zij reviseren op basis van peerfeedback in vergelijking met de leerlingen uit de controleklas. Dit is een direct gevolg van de verbeterde feedbackkwaliteit na de feedbackinstructie.

Background and Purpose-Induced hypertension is widely used to treat delayed cerebral ischemia (DCI) after aneurysmal subarachnoid hemorrhage, but a literature review shows that its presumed effectiveness is based on uncontrolled caseseries only. We here report clinical outcome of aneurysmal subarachnoid hemorrhage patients with DCI included in a randomized trial on the effectiveness of induced hypertension. Methods-Aneurysmal subarachnoid hemorrhage patients with clinical symptoms of DCI were randomized to induced hypertension or no induced hypertension. Risk ratios for poor outcome (modified Rankin Scale score >3) at 3 months, with 95% confidence intervals, were calculated and adjusted for age, clinical condition at admission and at time of DCI, and amount of blood on initial computed tomographic scan with Poisson regression analysis. Results-The trial aiming to include 240 patients was ended, based on lack of effect on cerebral perfusion and slow recruitment, when 21 patients had been randomized to induced hypertension, and 20 patients to no hypertension. With induced hypertension, the adjusted risk ratio for poor outcome was 1.0 (95% confidence interval, 0.6-1.8) and the risk ratio for serious adverse events 2.1 (95% confidence interval, 0.9-5.0). Conclusions-Before this trial, the effectiveness of induced hypertension for DCI in aneurysmal subarachnoid hemorrhage patients was unknown because current literature consists only of uncontrolled case series. The results from our premature halted trial do not add any evidence to support induced hypertension and show that this treatment can lead to serious adverse events.

Background: Extracorporeal life support (ECLS) is used to support the cardiorespiratory function in case of severe cardiac and/or respiratory failure in critically ill patients. According to the ELSO guidelines ECLS should be considered when estimated mortality risk approximates 80%. ECLS seems an efficient therapy in terms of survival benefit, but no undisputed evidence is delivered yet. The aim of the study is to assess the health-related quality of life after ECLS treatment and its cost effectiveness. Methods: We will perform a prospective observational cohort study. All adult patients who receive ECLS in the participating centers will be included. Exclusion criteria are patients in whom the ECLS is only used to bridge a procedure (like a high risk percutaneous coronary intervention or surgery) or the absence of informed consent. Data collection includes patient characteristics and data specific for ECLS treatment. Severity of illness and mortality risk is measured as precisely as possible using measurements for the appropriate age group and organ failure. For analyses on survival patients will act as their own control as we compare the actual survival with the estimated mortality on initiation of ECLS if conservative treatment would have been continued. Survivors are asked to complete validated questionnaires on health related quality of life (EQ5D-5 L) and on medical consumption and productivity losses (iMTA/iPCQ) at 6 and 12 months. Also the health related quality of life 1 month prior to ECLS initiation will be obtained by a questionnaire, if needed provided by relatives. With an estimated overall survival of 62% 210 patients need to be recruited to make a statement on cost effectiveness for all ECLS indications. Discussion: If our hypothesis that ECLS treatment is cost-effective is confirmed by this prospective study this could lead to an even broader use of ECLS treatment.

Objective To develop and validate a set of practical prediction tools that reliably estimate the outcome of subarachnoid haemorrhage from ruptured intracranial aneurysms (SAH). Design Cohort study with logistic regression analysis to combine predictors and treatment modality. Setting Subarachnoid Haemorrhage International Trialists' (SAHIT) data repository, including randomised clinical trials, prospective observational studies, and hospital registries. Participants Researchers collaborated to pool dataset

The purpose of the present study was to correlate the wavelength of the irradiation source with the phototoxic activity of tetra(m-hydroxyphenyl)chlorin (mTHPC) in healthy and neoplastic mucosae. The hamster tumour model for early squamous cell carcinoma was used in these experiments. In vitro and in vivo studies have shown that mTHPC absorbs significantly at 652 nm (1, 2). This wavelength is used currently in clinical mTHPC photodynamic therapy (PDT) trials. In order to study the wavelength dependence of the phototoxic effect on normal and tumour tissues, irradiation tests were performed 4 days after injection of 0.5mg kg-1 mTHPC. An argon-ion pumped dye laser was used as the light source. The light dose of 12 J cm-2 was delivered at a light dose rate of 150 mW cm-2. The wavelength was varied between 642.5 and 665 nm at 2.5-nm increments. The PDT damage was evaluated in serial Haematoxylin and Eosin stained sections using a tissue-damage scale. Light between 647.5 and 652.5 nm induced the highest damage to both the healthy and tumour mucosae. At wavelengths equal to or below 645 nm, and equal to or above 655 nm, tissue damage decreased. Wavelengths below 642 nm and above 660 nm did not induce any visible tissue damage. These results suggest that the in vivo optimal wavelength range for PDT with mTHPC is between 647 and 652 nm. This information is essential for selecting an appropriate light source

Tissue characterization by endoscopic fluorescence imaging of endogenous or exogenous fluorochromes is a promising method for early cancer detection. However, the steady-state fluorescence contrast between healthy tissue and lesions such as early-stage carcinomas is generally poor. The authors propose to improve this contrast by using the additional information contained in the fluorescence lifetime (FLT). The FLT of several fluorochromes is sensitive to their physico-chemical environment. The FLT can be measured by frequency-domain methods. The excitation light from a continuous wave (CW) laser is modulated in amplitude at radio-frequencies by an electro-optic modulator, and delivered to the tissue via an optical fibre. The endoscopie site is imaged by an endoscope on to an optical device. The gain of the fluorescence image detector is also modulated at the same frequency for homodyning. The tissue fluorescence image is recorded at several phases between the excitation and the detection modulations during an acquisition cycle. With these images, an image processor calculates the apparent FLT for each pixel and constructs a lifetime image of the endoscopie site. This process is performed at quasi-video frequencies. The influence of various physical parameters (modulation frequency, number of images by cycle, shot noise, tissue optical properties etc.) has been investigated by analytical analysis, simulation methods and experimentation. Preliminary results obtained on human tissues are also presented to illustrate the potentiality of the method

The prognosis of superficial bladder cancer in terms of recurrence and disease progression is related to bladder tumor multiplicity and the presence of concomitant "plane” tumors such as high-grade dysplasia and carcinoma in situ. This study in 33 patients aimed to demonstrate the role of fluorescence cystoscopy in transurethral resection of superficial bladder cancer. The method is based on the detection of protoporphyrin-IX-induced fluorescence in urothelial cancer cells by topical administration of 5-aminolevulinic acid. The sensitivity and the specificity of this procedure on apparently normal mucosa in superficial bladder cancer are estimated to be 82.9% and 81.3%, respectively. Thus, fluorescence cytoscopy is a simple and reliable method for mapping the bladder mucosa, especially in the case of multifocal bladder disease, and it facilitates the screening of occult dysplasia

We describe a new fluorescence imaging device for clinical cancer photodetection in hollow organs in which the tumor/normal tissue contrast is derived from the fluorescence lifetime of endogenous or exogenous fluorochromes. This fluorescence lifetime contrast gives information about the physicochemical properties of the environment which are different between normal and certain diseased tissues. The excitation light from a CW laser is modulated in amplitude at a radio frequency by an electrooptical modulator and delivered by an optical fiber through an endoscope to the hollow organ. The image of the tissue collected by the endoscope is separated in two spectral windows, one being the backscattered excitation light and the other the fluorescence of the fluorochrome. Each image is then focused on the photocathode of image intensifiers (II) whose optical gain is modulated at the same frequency as the excitation intensity, resulting in homodyne phase-sensitive images. By acquiring stationary phase-sensitive frames at different phases between the excitation and the detection, it is possible to calculate in quasi-real time the apparent fluorescence lifetime of the corresponding tissue region for each pixel. A result obtained by investigating the endogenous fluorochromes present in the mucous membrane of an excised human bladder is presented to illustrate this method and most of the optical parameters which are of major importance for this photodetection modality have been evaluated

Implementation of the pure-rotational Raman (PRR) lidar method for simultaneous measurement of atmospheric temperature, humidity, and aerosol extinction and backscatter coefficients is reported. The isolation of two wavelength domains of the PRR spectrum and the suppression of the elastically scattered light is carried out by a double-grating polychromator. Experiments involving elastic backscatter from dense clouds and a solid target confirm the high level of suppression of the elastic light in the corresponding acquisition channels of the two selected PRR domains. Calibration of the temperature channel was done both by comparison with an experimentally verified atmospheric temperature model profile and by inter-comparison with radiosondes. Night-time temperature profiles with high vertical resolution were obtained up to the lower stratosphere. The PRR temperature profile combined with the water vapor mixing ratio obtained from the ro-vibrational Raman channel is used to estimate the relative humidity

The aim of the present study was to monitor photodynamic angioocclusion with verteporfin in capillaries. Details of this process were recorded under a microscope in real-time using a high-sensitivity video camera. A procedure was developed based on intravenous (i.v.) injection of a light-activated drug, Visudyne®, into the chorioallantoic membrane (CAM) of a 12-day-old chicken embryo. The effect of light activation was probed after 24h by i.v. injection of a fluorescent dye (FITC dextran), and analysis of its fluorescence distribution. The angioocclusive effect was graded based on the size of the occluded vessels, and these results were compared with clinical observations. The time-resolved thrombus formation taking place in a fraction of the field of view was video recorded using a Peltier-cooled CCD camera. This vessel occlusion in the CAM model was reproducible and, in many ways, similar to that observed in the clinical use of verteporfin. The real-time video recording permitted the monitoring of platelet aggregation and revealed size-selective vascular closure as well as some degree of vasoconstriction. Platelets accumulated at intravascular junctions within seconds after verteporfin light activation, and capillaries were found to be closed 15min later at the applied conditions. Larger-diameter vessels remained patent. Repetition of these data with a much more sensitive camera revealed occlusion of the treated area after 5min with doses of verteporfin and light similar to those used clinically. Consequently, newly developed light-activated drugs can now be studied under clinically relevant conditions