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An extension of the theoretical formalism of Fresnel diffraction to the case of an inclined image plane is proposed. The resulting numerical algorithm speeds up computation times by typically three orders of magnitude, thus opening the possibility of utilizing previously inapplicable image analysis algorithms for this special type of a non shift-invariant imaging system. This is exemplified by adapting an iterative phase retrieval algorithm developed for electron microscopy to the case of hard x-ray imaging with asymmetric Bragg reflection (the so-called "Bragg Magnifier"). Numerical simulations demonstrate the convergence and feasibility of the iterative phase retrieval algorithm for the case of x-ray imaging with the Bragg Magnifier.

X-ray radiography is a common tool in the study of old master paintings. Transmission imaging can visualize hidden paint layers as well as the structure of the panel or canvas. In some medieval altarpieces, relics seem to have been imbedded in the wooden carrier of paintings. These are most probably thin organic fibrous materials such as paper or textile, which in traditional radiography are shadowed by the more absorbing surrounding material. This paper studies the application potential of synchrotron-based tomographic and laminographic imaging complemented with phase-contrast imaging for detection of such relics. The techniques are applied to a dummy painting. The results demonstrate that by using these imaging methods it is possible to three-dimensionally visualize hidden cavities in panels and detect thin fibrous low-Z materials sandwiched between a high-Z paint layer and a thick wooden panel.

Speckle pattern decorrelation reduces the accuracy of interferometric shape and deformation measurements. We introduce a technique for the reduction of speckle noise in digital holography. The method is not based on classical filtering techniques such as median filters. Instead it utilizes the shift theorem of the Fourier transform. For this method several holograms of the same object under test are recorded. The reconstruction leads to a set of object wave fields with different speckle patterns. A proper averaging procedure, taking into account the properties of the wrapped phases, leads to an improvement of the accuracy in the resulting phase difference. The theory of the applied method is described and our first results for technical components with an improvement of accuracy up to 1/57 of the wavelength are presented.

A method for the remote comparison of objects with regard to their shape or response to a load is presented. The method allows interferometric sensitivity for comparing objects with different microstructure. In contrast to the well-known incoherent techniques based on inverse fringe projection this new approach uses the coherent optical wave field of the master object as a mask for the illumination of the sample object. The coherent mask is created by digital holography to allow instant access to the complete optical information of the master object at any place desired. The mask is reconstructed by a spatial light modulator (SLM). The optical reconstruction of digital holograms with SLM technology allows modification of reconstructed wavefronts with respect to improvement of image quality, the skilled introduction of additional information about the object (augmented reality), and the alignment of the master and test object.

Fludarabine in combination with cyclophosphamide is an effective treatment for newly diagnosed as well as relapsed follicular lymphoma. The anti-CD20 antibody rituximab has been employed successfully for the same indications. No such data were available on a combined use of these agents. Therefore, we conducted a phase II study to evaluate the safety and efficacy of a combination of rituximab (375 mg/m2), fludarabine (4 x 25 mg/m2) and cyclophosphamide (1 x 750 mg/m2), for the treatment of relapsed follicular lymphoma. An unexpected, severe hematologic toxicity with significant, prolonged thrombocytopenias WHO grade III/IV in 6 (35%) of 17 patients treated in total occurred, leading to early termination of the trial. Cytologic and serologic analyses point toward a direct toxic effect. Older patients (mean age 64.7 vs. 56.5 yr) were significantly (P = 0.02) more likely to suffer from this toxicity, whereas no other clinical or hematologic parameter differed statistically between the patients suffering from thrombocytopenia and those who did not. The addition of rituximab to fludarabine/cyclophosphamide employed at doses given above in relapsed follicular lymphoma may have led to this increase in thrombocytopenias. Therefore, caution should be exercised when combining these drugs for the treatment of patients with relapsed follicular lymphoma, especially when treating older patients., (Copyright Blackwell Munksgaard 2004.)

We described a method for direct holographic comparison of the shape or the deformation of two objects when it is not necessary that both samples be located at the same place. In contrast to the well-known incoherent techniques based on inverse fringe projection, this new approach uses a coherent mask that is imaged onto a sample object that has a microstructure different from that of the master object. The coherent mask is created by digital holography to permit instant access to complete optical information on the master object at any wanted place. Transmission of the digital master holograms to the relevant places can be made with a broadband digital telecommunication network such as the Internet.