Roadmap on computational methods in optical imaging and holography [invited].

Unlabelled: Computational methods have been established as cornerstones in optical imaging and holography in recent years. Every year, the dependence of optical imaging and holography on computational methods is increasing significantly to the extent that optical methods and components are being completely and efficiently replaced with computational methods at low cost. This roadmap reviews the current scenario in four major areas namely incoherent digital holography, quantitative phase imaging, imaging through scattering layers, and super-resolution imaging.

Deep hologram converter from low-precision to middle-precision holograms.

We propose a deep hologram converter based on deep learning to convert low-precision holograms into middle-precision holograms. The low-precision holograms were calculated using a shorter bit width. It can increase the amount of data packing for single instruction/multiple data in the software approach and the number of calculation circuits in the hardware approach.

JPEG Pleno holography presents the numerical reconstruction software for holograms: an excursion in holographic views.

Digital reconstructions of numerical holograms enable data visualization and serve a multitude of purposes ranging from microscopy to holographic displays. Over the years, many pipelines have been developed for specific hologram types. Within the standardization effort of JPEG Pleno holography, an open-source MATLAB toolbox was developed that reflects the best current consensus.

Binary hologram compression using context based Bayesian tree models with adaptive spatial segmentation.

With holographic displays requiring giga- or terapixel resolutions, data compression is of utmost importance in making holography a viable technique in the near future. In addition, since the first-generation of holographic displays is expected to require binary holograms, associated compression algorithms are expected to be able to handle this binary format. In this work, the suitability of a context based Bayesian tree model is proposed as an extension to adaptive binary arithmetic coding to facilitate the efficient lossless compression of binary holograms.

Pincushion point-spread function for computer-generated holography.

Point-spread functions (PSFs) are non-stationary signals whose spatial frequency increases with the radius. These signals are only meaningful over a small spatial region when being propagated over short distances and sampled with regular sampling pitch. Otherwise, aliasing at steep incidence angles leads to the computation of spurious frequencies.

JPEG Pleno holography: scope and technology validation procedures.

JPEG Pleno is a standardization framework addressing the compression and signaling of plenoptic modalities. While the standardization of solutions to handle light field content is currently reaching its final stage, the Joint Photographic Experts Group (JPEG) committee is now preparing for the standardization of solutions targeting point cloud and holographic modalities. This paper addresses the challenges related to the standardization of compression technologies for holographic content and associated test methodologies.

Suitability analysis of holographic vs light field and 2D displays for subjective quality assessment of Fourier holograms.

Measuring the impact of compression on the reconstruction quality of holograms remains a challenge. A public subjectively-annotated holographic data set that allows for testing the performance of compression techniques and quality metrics is presented, in addition to a subjective visual quality assessment methodology. Moreover, the performance of the quality assessment procedures is compared for holographic, regular 2D and light field displays.

Exploration of a novel virtual environment improves memory consolidation in ADHD.

Experimental evidence in rodents and humans suggests that long-term memory consolidation can be enhanced by the exploration of a novel environment presented during a vulnerable early phase of consolidation. This memory enhancing effect (behavioral tagging) is caused by dopaminergic and noradrenergic neuromodulation of hippocampal plasticity processes. In translation from animal to human research, we investigated whether behavioral tagging with novelty can be used to tackle memory problems observed in children and adolescents with attention-deficit/hyperactivity disorder (ADHD).

Object-based digital hologram segmentation and motion compensation.

Digital video holography faces two main problems: 1) computer-generation of holograms is computationally very costly, even more when dynamic content is considered; 2) the transmission of many high-resolution holograms requires large bandwidths. Motion compensation algorithms leverage temporal redundancies and can be used to address both issues by predicting future frames from preceding ones. Unfortunately, existing holographic motion compensation methods can only model uniform motions of entire 3D scenes.

Efficient holographic video generation based on rotational transformation of wavefields.

High-quality holographic video generation requires both high computational resources and time; therefore, algorithms that can generate holographic videos efficiently will be soon in demand for dynamic holographic 3D displays. In this work, we present two algorithms that use a motion compensation scheme - based on the rotational transformation of wavefields [Appl. Opt.

Exact global motion compensation for holographic video compression.

Holographic video requires impractical bitrates for storage and transmission without data compression. We introduce an end-to-end compression pipeline for compressing holographic sequences with known ground truth motion. The compression strategy employs a motion compensation algorithm based on the rotational transformation of an angular spectrum.

APRIL and BAFF: novel biomarkers for central nervous system lymphoma.

Background: Early diagnosis of CNS lymphoma (CNSL) is essential for successful therapy of this rapidly progressing brain tumor. However, in patients presenting with focal brain lesions, fast and reliable diagnosis of PCNSL remains a challenge. A proliferation-inducing ligand (APRIL) and B cell activating factor (BAFF) are important factors in the pathophysiology, diagnosis, and prognosis of systemic B cell malignancies.

Wave atoms for digital hologram compression.

Compression of macroscopic digital holograms is a major research problem, which if unresolved will continue to limit the possible applications of holography in multimedia contexts. The quest of searching for the most suitable representation for compression is still an open problem. In this work, we study sparsification by the wave atom transform, introduced in 2006 by Demanet et al.

Randomized phase III study of whole-brain radiotherapy for primary CNS lymphoma.

Objective: This is the final report of a phase III randomized study to evaluate whole-brain radiotherapy (WBRT) in primary therapy of primary CNS lymphoma (PCNSL) after a median follow-up of 81.2 months.

Methods: Patients with newly diagnosed PCNSL were randomized to high-dose methotrexate (HDMTX)-based chemotherapy alone or followed by WBRT.

Prognostic impact of intraocular involvement in primary CNS lymphoma: experience from the G-PCNSL-SG1 trial.

The impact of intraocular involvement (IOL) in primary CNS lymphoma (PCNSL) has not been sufficiently evaluated. Here, we present the analysis of IOL in the only completed randomized phase III trial in PCNSL. The G-PCNSL-SG1 study evaluated the role of whole-brain radiotherapy in primary therapy of PCNSL.

Optical and magneto-optical properties of metal phthalocyanine and metal porphyrin thin films.

The optical constants together with the magneto-optical Voigt constants of several phthalocyanine (Pc) and methoxy functionalized tetraphenylporphyrin (TMPP) thin films prepared on silicon substrates are presented. The materials investigated are MePc with Me = Fe, Co, Ni, Cu, Zn and MeTMPP with Me = Cu, Ni. We also compared our results to the metal-free H2Pc, H2TPP and H2TMPP.

Successful long-term control of lymphomatous meningitis with intraventricular rituximab.

Most primary central nervous system lymphomas (PCNSL) are highly malignant B-cell non-Hodgkin lymphomas. First-line therapy consists of high-dose methotrexate-based chemotherapy with or without whole brain radiotherapy. However, no standard of care is defined for refractory or recurrent PCNSL.

Expression of B-cell activating factor, a proliferating inducing ligand and its receptors in primary central nervous system lymphoma.

B-cell activating factor belonging to the tumor necrosis factor family (BAFF) and a proliferating inducing ligand (APRIL) might play an important role in the pathogenesis of systemic B-cell malignancies. However, the BAFF/APRIL system has not been systematically evaluated in primary central nervous system lymphoma (PCNSL) to date. We assessed the expression of BAFF, APRIL and its receptors BAFF-R (BAFF receptor), BCMA (B-cell maturation antigen) and TACI (transmembrane activator and calcium modulator cyclophilin ligand interactor) in five PCNSL specimens by immunohistochemical staining.

Early relapses in patients with primary CNS lymphoma treated with methotrexate-based chemotherapy without consolidating whole brain irradiation.

Methotrexate (MTX)-based chemotherapy is used as upfront treatment for most patients with primary CNS lymphoma. Whether consolidating whole brain irradiation (WBI) should be recommended for patients who achieve complete remission (CR) is still a matter of debate. Patients who are predicted to experience an early relapse (ER, ≤12 months from diagnosis) might especially benefit from consolidating treatment.

Rituximab significantly improves complete response rate in patients with primary CNS lymphoma.

Rituximab improves outcome for patients with systemic diffuse large B-cell lymphoma (DLBCL) and has therefore become a standard component of the treatment of this disease. However, it is unclear whether rituximab is efficacious in patients with primary CNS lymphoma (PCNSL), a rare DLBCL variant, also. The purpose of this study was to evaluate the effect of rituximab on the complete response (CR) rate after chemotherapy with methotrexate (MTX) and ifosfamide (IFO) of patients with PCNSL.

"Moderate intensive insulin therapy" is associated with remission of high intracranial pressure in patients with vascular or infectious central nervous system diseases.

Intensive insulin therapy (IIT), targeting blood glucose between 80 mg/dL and 110 mg/dL ("strict IIT"), has been associated with rapid remission of high intracranial pressure (ICP), but its use is limited due to a high risk of hypoglycemia. The aim of this retrospective study was to assess whether "moderate IIT" (target range for blood glucose: 80-140 mg/dL) could have the same beneficial effect on ICP with a lower risk of hypoglycemia. We retrospectively analyzed the records of 64 patients with high ICP due to vascular or infectious central nervous system diseases.

Prognostic impact of meningeal dissemination in primary CNS lymphoma (PCNSL): experience from the G-PCNSL-SG1 trial.

Background: We evaluated the frequency and prognostic impact of meningeal dissemination (MD) in immunocompetent adult patients with primary central nervous system lymphoma treated in a randomized phase III trial.

Patients And Methods: MD was evaluated at study entry and defined by lymphoma proof in the meningeal compartment detected by at least one of the following methods: cerebrospinal fluid (CSF) cytomorphology, detection of clonal B cells by IgH PCR in CSF or contrast enhancement of the leptomeninges on magnetic resonance imaging (MRI).

Results: Data on MD were available in 415 patients, of those, MD was detected in 65 (15.

The crossed leg sign indicates a favorable outcome after severe stroke.

Objective: We investigated whether crossed legs are a prognostic marker in patients with severe stroke.

Methods: In this controlled prospective observational study, we observed patients with severe stroke who crossed their legs during their hospital stay and matched them with randomly selected severe stroke patients who did not cross their legs. The patients were evaluated upon admission, on the day of leg crossing, upon discharge, and at 1 year after discharge.