41 research outputs found

    Fast fluorescence microscopy for imaging the dynamics of embryonic development

    Get PDF
    Live imaging has gained a pivotal role in developmental biology since it increasingly allows real-time observation of cell behavior in intact organisms. Microscopes that can capture the dynamics of ever-faster biological events, fluorescent markers optimal for in vivo imaging, and, finally, adapted reconstruction and analysis programs to complete data flow all contribute to this success. Focusing on temporal resolution, we discuss how fast imaging can be achieved with minimal prejudice to spatial resolution, photon count, or to reliably and automatically analyze images. In particular, we show how integrated approaches to imaging that combine bright fluorescent probes, fast microscopes, and custom post-processing techniques can address the kinetics of biological systems at multiple scales. Finally, we discuss remaining challenges and opportunities for further advances in this field

    Focusing and Compression of Ultrashort Pulses through Scattering Media

    Full text link
    Light scattering in inhomogeneous media induces wavefront distortions which pose an inherent limitation in many optical applications. Examples range from microscopy and nanosurgery to astronomy. In recent years, ongoing efforts have made the correction of spatial distortions possible by wavefront shaping techniques. However, when ultrashort pulses are employed scattering induces temporal distortions which hinder their use in nonlinear processes such as in multiphoton microscopy and quantum control experiments. Here we show that correction of both spatial and temporal distortions can be attained by manipulating only the spatial degrees of freedom of the incident wavefront. Moreover, by optimizing a nonlinear signal the refocused pulse can be shorter than the input pulse. We demonstrate focusing of 100fs pulses through a 1mm thick brain tissue, and 1000-fold enhancement of a localized two-photon fluorescence signal. Our results open up new possibilities for optical manipulation and nonlinear imaging in scattering media

    Product Data Management – Defining the Used Terms

    No full text
    Part 9: Knowledge EngineeringInternational audienceThe Product Data Management (PDM) system and its associated terminology have changed over the years. Product Lifecycle Management (PLM) has become the predominant system and tends to overshadow PDM. However, PDM remains relevant and is a system commonly used by design engineers; mainly as a storage place for drawings and a place where drawings can be found for further editing.To obtain full benefit from the PDM/PLM systems, precise definitions are required. Without such definitions, the systems cannot function as they should and they cannot be used optimally. Furthermore, shortcomings in definitions may lead to a situation where the engineering community is unaware of the kind of help the systems can offer.The main focus of this conference paper is definition of some of the terms inherent to PDM/PLM systems and their data

    Adaptive wavefront correction in two-photon microscopy using coherence-gated wavefront sensing

    No full text
    The image quality of a two-photon microscope is often degraded by wavefront aberrations induced by the specimen. We demonstrate here that resolution and signal size in two-photon microcopy can be substantially improved, even in living biological specimens, by adaptive wavefront correction based on sensing the wavefront of coherence-gated backscattered light (coherence-gated wavefront sensing, CGWS) and wavefront control by a deformable mirror. A nearly diffraction-limited focus can be restored even for strong aberrations. CGWS-based wavefront correction should be applicable to samples with a wide range of scattering properties and it should be possible to perform real-time pixel-by-pixel correction even at fast scan speeds

    Digital Technical and Informal Resources of Breast Cancer Patients From 2012 to 2020: Questionnaire-Based Longitudinal Trend Study

    No full text
    Background: Digitalization offers enormous potential in medicine. In the era of digitalization, the development of the use of digital, technical, and informal resources of breast cancer patients and factors influencing the degree of digitization of patients has been insufficiently researched. Objective: The aim of this study was to assess the development of the use of digital technical and informal resources in a well-defined patient cohort. Methods: A longitudinal study on 513 breast cancer patients from 2012 to 2020 was conducted using a questionnaire that included the main aspects of the degree of digitalization, including digital device availability and use, stationary and mobile internet access and use, and communication and information seeking regarding breast cancer diagnosis and treatment. Results: The majority of patients (421/513, 82.1%) owned the technical resources to benefit from eHealth, used the internet to obtain information (292/509, 57.4%), and were willing to use new eHealth solutions (379/426, 89%). Two-thirds of the patients discussed information about their cancer on the internet with their doctor, one-third found additional treatment options on the internet, and 15.3% (44/287) of the patients stated that this had changed their cancer therapy. The degree of digitization is increasing yet still significantly depends on 3 factors: (1) age (whereas 100% [39/39] of the 70-year-old group used the internet), (2) education (internet use significantly depended on education, as only 51.8% [59/114] of patients with primary school education used the internet, but 82.4% [126/153] with middle school education and 90.3% [213/236] with high school education used the internet; P= 2 people used the internet; P<.001). Conclusions: To implement digital solutions in health care, knowledge of the composition and degree of the use of digital technical and informal resources of the patient group for which the respective solution is developed is crucial for success

    An innovative and efficient method to control the shape of push-pull membrane deformable mirror

    No full text
    We carry out performance characterisation of a commercial push and pull deformable mirror with 48 actuators (Adaptica Srl). We present a detailed description of the system as well as a statistical approach on the identification of the mirror influence function. A new efficient control algorithm to induce the desired wavefront shape is also developed and comparison with other control algorithms present in literature has been made to prove the efficiency of the new approach.IST/Imaging Science and TechnologyApplied Science
    corecore